Enhanced External Counterpulsation Improves Peripheral Artery Flow-Mediated Dilation in Patients with Chronic Angina
Randy Braith, PhD, C. Richard Conti, MD; Wilmer Nicholas, PhD; Calvin Y. Choi, MD; Matheen Khuddus, MD; Darren T. Beck, MS; Darren P. Casey, PhD.
A Randomized Sham-Controlled Study
From the Department of Applied Physiology and Kinesiology, College of Health and Human Performance (R.W.B., D.T.B.) and Division of Cardiovascular Medicine, College of Medicine, (R.W.B, C.R.C.,W.W.N.,C.Y.C.,M.A.K.), University of Florida, Gainesville; and Department of Anesthesiology, Mayo Clinic, Rochester, MN (D.P.C.)
Circulation2010; 122:1612-1620
Published online before October 4, 2010. 10.1161/CIRCULATIONAHA.109.923482.
BACKGROUND
Mechanisms responsible for anti-ischemic benefits of enhanced external counterpulsation (EECP) remain unknown. This was the first randomized sham-controlled study to investigate the extracardiac effects of EECP on peripheral artery flow-mediated dilation
METHODS and RESULTS
Forty-two symptomatic patients with coronary artery disease were randomized (2:1 ratio) to thirty-five 1-hour sessions of either EECP (n=28) or sham EECP (n=14). Flow-mediated dilation of the brachial and femoral arteries was performed with the use of ultrasound. Plasma levels of nitrate and nitrite, 6-keto-prostaglandin F1a, endothelin, asymmetrical dimethylarginine, tumor necrosis factor -a, monocyte chemoattractant protein-1, soluble vascular cell adhesion molecule, high sensitivity C-reactive protein, and 8-isoprostane were measured. EECP increased brachial (+51% versus +2%) and femoral (+30% versus +3%) artery flow-mediated dilation, the nitric oxide turnover/production makers nitrate and nitrite (+36% versus +2%), and 6-keto prostaglandin F1a(+71% versus +1%), whereas it decreased endothelin-1 (-25% versus +5%) and the nitric oxide synthase inhibitor asymmetrical dimethylarginine (-28% versus +0.2%) in treatment versus sham groups, respectively (all P<0.05). EECP decreased the proinflammatory cytokines tumor necrosis factor -a(-16% versus +12%), monocyte chemoattractant protein-1 (-13% versus +0.2%), soluble vascular cell adhesion molecule-1 (-6% versus +1%, high sensitivity C-reactive protein (-32% versus +5%), and the lipid peroxidation marker 8-isoprostane (-21% versus +1.3%) in treatment versus sham groups, respectively (all P<0.05). EECP reduced angina classification (-62% versus 0%; P<0.001) in treatment versus sham group, respectively.
CONCLUSION
Our findings provide novel mechanistic evidence that EECP has a beneficial effect on peripheral artery flow-mediated dilation and endothelial-derived vasoactive agents in patients with symptomatic coronary artery disease.
Enhanced External Counterpulsation and Future Directions: Step Beyond Medical Management for Patients with Angina and Heart Failure
Manchanda, Aarush and Soran, Ozlem.
Journal of American College of Cardiology 2007;50:1523-31.
Department of Internal Medicine, The George Washington University, Washington D.C.; and the Cardiovascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
Between 25,000 and 75,000 new cases of angina refractory to maximal medical therapy and standard coronary revascularization procedures are diagnosed each year. In addition, heart failure also places an enormous burden on the U.S. Health care system, with an estimated economic impact ranging from $20 billion to more than $50 billion per year. The technique of counterpulsation, studied for almost one-half century now, is considered a safe, highly beneficial, low-cost, non-invasive treatment for these angina patients, and now for heart failure patients as well. Recent evidence suggests that enhanced external counterpulation (EECP) therapy may improve symptoms and decrease long-term morbidity via more than 1 mechanism, including improvement in endothelial function, promotion of collateralization, enhancement of ventricular function, improvement in oxygen consumption (Vo2), regression of atherosclerosis, and peripheral training effects similar to exercise. Numerous clinical trials in the last 2 decades have shown EECP therapy to be safe and effective for patients with refractory angina with clinical response rate averaging 70% to 80%, which is sustained up to 5 years. It is not only safe in patients with coexisting heart failure, but also is shown to improve quality of life and exercise capacity and to improve left ventricular function long term. Interestingly, EECP therapy has been studied for various potential uses other than heart disease, such as restless leg syndrome, sudden deafness, hepatorenal syndrome, erectile dysfunction, and so on. This review summarizes the current evidence for its use in stable angina and heart failure and its future direction.
Impact of External Counterpulsation Treatment on Emergency Department Visits and Hospitalizations in Refractory Angina Patients with Left Ventricular Dysfunction
Soran Ozlem, Kennard Elizabeth, Bart Bradley, and Kelsey Sheryl
Congestive Heart Failure. 2007; 13:36-40.
Cardiovascular Institute, University of Pittsburgh Medical Center; the Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA; and Hennepin County Medical Center, Minneapolis, MN.
Patients with refractory angina and left ventricular (LV) dysfunction exert an enormous burden on health care resources primarily because of the number of recurrent emergency department (ED) visits and hospitalizations. Enhanced External Counterpulsation (EECP) therapy has emerged as a treatment option for patients with angina and LV dysfunction and has been shown to improve clinical outcomes and LV function. Improvements in symptoms and laboratory assessments in these patients, however, do not necessarily correlate with a reduction in ED visits and hospitalizations. This is the first study to assess the impact of EECP therapy on ED visits and hospitalization rates at 6 month follow-up. This prospective cohort study included 450 patients with LV dysfunction (ejection fraction≤40%) treated with EECP therapy for refractory angina. Clinical outcomes, number of all-cause ED visits, and hospitalization within the 6 months before EECP were compared with those at 6 month follow-up. Despite the unfavorable risk profile, refractory angina patients with LV dysfunction achieved a substantial reduction in all-cause ED visits and hospitalization rates at 6 month follow-up. EECP therapy offers an effective adjunctive treatment options for this group of patients.
Effects of external counterpulsation in plasma nitric oxide and endothelin-1 levels
Akthar M, Wu GF, Du ZM, Zheng ZS, Michaels AD
Department of Medicine, Division of Cardiology, University of California at San Francisco Medical Center, USA
Am J Cardiol. 2006 Jul 1; 98(1):28-30. Epub 2006 May 3.
Enhanced external counterpulsation (EECP) significantly augments diastolic blood flow and has been postulated to improve endothelial function by increased shear stress. We examined the effects of EECP on plasma nitric oxide and endothelin-1 (ET-1) levels. Plasma nitrate and nitrite (NOx) and ET-1 levels were measured serially in 13 patients with coronary artery disease who received 1-hour daily treatments of EECP over six weeks. During the course of EECP therapy, plasma NOx progressively increased and plasma ET-1 progressively decreased. After 36 hours of EECP, there was a 62+/- 17% increase in plasma NOx compared with the baseline (43.6 =/- 4.3 vs 27.1 +/- 2.6 mumol/L, p Our data provides neurohormonal evidence to support hypothesis that EECP improves endothelial function.
One year follow-up of patients with refractory angina pectoris treated with enhanced external counterpulsation
Thomas Pettersson, Susanne Bondesson, Diodor Cojocaru, Ola Ohlsson, Angelica Wackenfors and Lars Edvinsson
BMC Cardiovacular Disorders 2006, 6:28 doi:10.1186/1471-2261-6-28
Published 15 June 2006
Abstract (Provisional)
BACKGROUND: Enhanced external counterpulsation (EECP) is a non-invasive technique that has been shown to be effective in reducing both angina and myocardial ischemia in patients not responding to medical therapy and without revascularization alternatives. The aim of the present study was to assess the long term outcome of EECP treatment at a Scandinavian centre, in relieving angina in patients with chronic refractory angina pectoris.
METHODS: 55 patients were treated with EECP. Canadian cardiovascular society (CCS) class, antianginal medication and adverse clinical events were collected prior to EECP, at the end of treatment, and at six and 12 months after EECP treatment. Clinical signs and symptoms were recorded.
RESULTS: EECP treatment significantly improved the CCS class 79.6% of the patients with chronic angina pectoris (p>0.001). The reduction in CCS angina class was seen in patients with CCS class III and IV and persisted 12 months after EECP treatment. There was no significant relief in angina in patients with CCS class after EECP treatment. 73.7% of the patients with a reduction in CCS class after EECP treatment improved one or CCS class, and 22.7% of the patients improved two CCS classes. The improvement of two classes could progress over a six month period and tended to be more prominent in patients with CCS class IV. In accordance with the reduction in CCS classes there was a significant decrease in the weekly nitroglycerin usage (p> 0.05).
CONCLUSIONS: The results from the present study show that EECP is a safe treatment for highly symptomatic patients with refractory angina. The beneficial effects were sustained during a 12 month follow-up period.
Enhanced external counterpulsation for treatment of refractory angina pectoris. [Journal Article]
Novo G, Bagger JP, Carta R, Koutroulis G, Hall R, Nihoyannopoulos P
J Cardiovasc Med (Hagerstown) 2006 May; 7(5): 335-339.
OBJECTIVE: Enhanced external counterpulsation (EECP) is a noninvasive, well tolerated treatment, effective for managing patients with refractory angina pectoris. The aim of this study was to evaluate the efficacy of EECP to relieve symptoms, to decrease myocardial ischemia and to improve cardiac performance in patients with intractable angina, refractory to surgical and medical treatment.
METHODS: Twenty-five patients (24 men and one woman, mean age 65 years) with persistent ischemia notwithstanding optimal medical therapy or after interventional or surgical procedure, received EECP sessions for 35 h. Each patient underwent dobutamine stress echocardiography before and after treatment. We evaluated modifications in either cardiac systolic or diastolic function, and in wall motion score index.
RESULTS: Eighty four percent of patients showed an increase in at least one functional angina class. We did not observe any significant changes in fractional shortening and diastolic function. Thirty-six percent of patients had a reduction in the area of inducible ischemia at dobutamine stress echocardiography after treatment. Unfortunately, because of small sample size, we did not find any statistically significant difference. There was a trend showing that patients who benefited the most were those with worst systolic function and with severely compromised segmental kinesis (P=NS).
CONCLUSIONS: EECP is effective in relieving symptoms in patients with refractory angina and may reduce inducible ischemia at dobutamine stress echocardiography, especially in patients with reduced systolic function and compromised segmental kinesis.
AM J Cardiol 2002 May 15;89(10):1182-6
Comparison of patients undergoing enhanced external counterpulsation and percutaneous coronary intervention for stable angina pectoris.
Holobkov R, Kennard ED, Foris JM, Kelsey SF, Soran O, Willams DO, Holmes DR.
Department of Epidemiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
External Counterpulsation (ECP), a treatment option for angina patients, may be a reasonable treatment strategy for revascularization with percutaneous coronary intervention (PCI). We compared baseline characteristics and 1-year outcome in 2 cohorts of PCI candidates presenting with stable symptoms: 323 patients treated with ECP in the International EECP Patient Registry (IEPR), and 448 NHLBI Dynamic Registry patients treated with elective PCI. Compared with patients receiving PCI, IEPR patients had a higher prevalence of many risk factors including prior PCI (53.0% vs 33.3%, p<0.001), prior coronary artery bypass grafting (42.1% vs 18.6%, p<0.01), prior myocardial infarction (56.4% vs 27.8%, p<0.001), history of congestive heart failure (16.8% vs 9.2%, p<0.01), and history of diabetes (37.9% vs 23.5%, p<0.001). Left ventricular ejection fraction was lower among IEPR patients (mean 50.3% vs 59.2%. p<0.001). At 1 year, survival was comparable in the 2 cohorts (98.7% IEPR vs 96.8% PCI, p=NS), as were rates at coronary artery bypass grafting during follow-up (4.5% IEPR vs 5.7% PCI, p=NS). At 1 year, 43.7% of IEPR patients reported no anginal symptoms compared with 73.4% of Dynamic Registry patients (p<0.001). Rates of severe symptoms (Canadian Cardiovascular Society class III, IV, or unstable) at 1 year were 15.5% among IEPR patients and 9.5% in the Dynamic Registry (p=0.02). PCI candidates suitable for and treated with ECP had 1-year major event rates comparable to patients receiving elective PCI. Although PCI was associated with substantially lower rates of 1-year symptoms, ECP may be a safe treatment option for selected patients with coronary artery disease.
AM J Cardiol 2002 Apr 1;89(7):822-4
Effects of enhanced external counterpulsation on stress radionuclide coronary perfusion and exercise capacity in chronic stable angina pectoris.
Stys TP, Lawson WE, Hui JC, Fleishman B, Manzo, Strobeck Je, Tartaglia J, Ramasamy S, Suwita R, Zheng ZS, Liang H, Werner D.
State University of New York at Stony Brook, New York 11794, USA.
External Counterpulsation (ECP) is an effective noninvasive procedure for patients with coronary artery disease (CAD). ECP has been shown to improve anginal class and time to ST-segment depression during exercise stress testing. This study evaluates the efficacy of ECP in improving stress-induced myocardial ischemia using radionuclide perfusion treadmill stress test (RPSTs). The international study group enrolled patients from 7 centers with chronic stable angina pectoris and a baseline ischemia pre-ECP RPST. Clinical characteristics and the patients’ demographics were recorded. A baseline pre-ECP, whereas 3 centers performed maximal RPST was executed within one month before ECP treatment. The results were compared with a follow-up RPST performed within 6 months of completion of a 35-hour course of ECP. Four centers performed after ECP RPST to the same level of exercise as pre-ECP whereas 3 centers performed maximal RPST post-ECP. The study enrolled 175 patients (155 men and 20 women). Improvement in angina, defined by > or =1 Canadian Cardiovascular Society angina class change, was reported 85% of patients, in the centers performing the same level of exercise, 81 of 97 patients (83%) had significant improvement in RPST perfusion images. Patients who underwent maximal RPST revealed improvement in exercise duration (6.61 +/- 1.88 pre-ECP vs 7.41 +/- 2.03 minutes after ECP, p<0.0001); 42 of the 78 patients (54%) in this group showed significant improvement in RPST perfusion images. Therefore, ECP was effective in improving stress myocardial perfusion in patients with chronic stable angina at both comparable (baseline) and at maximal exercise levels.
J Investig Med 2001 Nov;49(6):500-4
Acute and chronic hemodynamic effects of enhanced external counterpulsation in patients with angina pectoris
Arora RR, Carlucci ML, Malone AM, Baron NV.
Department of Medicine, University of Medicine and Dentistry of New Jersey, Newark, USA. aroras@umdnj.edu
BACKGROUND: External Counterpulsation (ECP) is an effective noninvasive treatment for patients with angina pectoris. The hemodynamic effects of ECP are not yet known and have been theorized to simulate the clinical use of the intra-aortic balloon pump, enhancing cardiac output, stroke volume, and retrograde aortic diastolic flow.
METHODS: Twelve hemodynamic parameters were measured, using the BioZ System (CardioDynamics International Corporation, San Diego, Calif) after 1 hour (n=22) and after 35 hours (n=16) of ECP treatment compared with baseline. The BioZ System non-invasively measures hemodynamics parameters using the thoracic electrical bioimpedance method.
RESULTS: One hour of ECP treatment showed a significant decrease in cardiac output, stroke volume, contractility, afterload, preload, and myocardial energy production, but systolic time ratios and thoracic fluid content were unchanged. After 35 hours of therapy, stroke volume (P<or=0.05), index of contractility (P<or =0.05), and thoracic fluid content (P<or=0.01) were decreased.
CONCLUSIONS: The acute reduction in contractility, preload, and concurrent bradycardia may have favorable hemodynamic effects for patients with angina pectoris. Even further studies would be beneficial to elucidate the mechanism of ECP therapy and its efficacy for patients with angina pectoris.
Angiology 2001 Oct;52(10):653-8
Acute hemodynamic effects and angina improvement with enhanced external counterpulsation.
Stys T, Lawson WE, Hui JC, Lang G, Liuzzo J, Cohn PF.
Department of Surgery, SUNY at Stony Brook, NY, USA.
External Counterpulsation is a noninvasive treatment for coronary artery disease. The mechanism of action is thought to be hemodynamic. The complex hemodynamic effects have been simply quantified by calculating a previously described effectiveness ratio (ER). The EECP Clinical Consortium, a clinical registry of 37 centers, prospectively enrolled 395 chronic stable angina patients (79 women, 316 men, mean age 66 years) to examine the relation of the ER to post-treatment improvement in Canadian Cardiovascular Society angina class (CCS). Women and the elderly underwent planned subgroup analysis. The ER was computed during the first and last hours of a 35-hour course of ECP treatment. After ECP, CCS improved by at least 1 class in 88% of patients, 87% of men and 92% of women (p=NS), and in 89% of patients < or = 66 years old (p=NS). The first and final ER was similar in patients with and without improvement in CCS. Significant first-hour ER differences were seen between men and women (0.96 +/- 0.03 vs 0.76 +/- 0.04, p<0.005), and between ages < or + 66 and > 66 years old (1.04 +/- 0.04 vs 0.81 +/- 0.03, p<0.0001). However, all subgroups responded equally in men and women and across a broad range of ages. The hemodynamic effect of ECP (ER) does not predict improvement in CCS and may indicate that other factors, such as neurohormonal changes, could have a significant role in mediating the observed ECP benefits.
Psychosomatic 2001 Mar-April;42(2):124-32
Psychosocial effects of enhanced external counterpulsation in the angina patient: a second study.
Springer S, Fife A, Lawson W, Hui JC, Jandorf L, Cohn PF, Fricchione G.
Department of Psychiatry, Massachusetts General Hospital, Boston 02114-2696, USA.
External Counterpulsation (ECP) is a noninvasive method that has demonstrated promise in the treatment of ischemic coronary artery disease. Patients who underwent ECP were tested for alterations in psychosocial state associated with treatment. As a whole, patients’ quality of life and perception of health improved. Notable improvements in levels of depression, anxiety, and somatization were detected but no change in the levels of anger or hostility were noted. On most measures, change was more significant for subjects who showed objective evidence of resolution ischemia. Knowing the predictive relationship between depression and mortality from cardiac disease, the improvement in depression scores through ECP shows a finding of potential significance that may warrant further study in future research.
Curr Interv Cardiol Rep 2001 Feb;3(1):37-43
Enhanced External Counterpulsation in Unrevascularizable Patients.
Barsness GW.
Mayo Clinic and Foundation, 200 First Street, SW, Rochester, MN 55905, USA. barsness.gregory@mayo.edu
External Counterpulsation (ECP) is a noninvasive outpatient therapy for the treatment of chronic angina. ECP produces an acute hemodynamic effect that is similar to the invasive intra-aortic balloon pump. Three sets of cuffs on the upper thigh, lower thigh, and calves of each leg inflate with compressed air during the diastolic phase of the cardiac cycle and deflate in early systole. This quick inflation and deflation raises diastolic aortic pressure, increases coronary perfusion pressure, and gives improved afterload reduction and increased venous return with a subsequent increase in cardiac output. External Counterpulsation provides long-term symptom relief in patients with ischemic heart disease in several case series, and in a randomized trial. Up to 80% of patients chosen for treatment have a positive clinical response, and an associated objective improvement has been shown by functional imaging in many case series. Treatment course is comprised of 35 1-hour sessions lasting a 7-week period. This is usually tolerable with a low risk of harmful events. Development and enhancement of collateral channels, as well as peripheral conditioning and neurohumoral effects, may play a role in providing symptomatic relief. Studies are ongoing to determine the mechanism of action and to further define subsets of patients who might beat an advantage.
J Am Coll Cardiol 2001 Jan; 37(1):93-9
Enhanced external counterpulsation improves exercise tolerance, reduces exercise-induced myocardial ischemia and improves left ventricular diastolic filling in patients with coronary artery disease.
Urano H, Ikeda H, Ueno T, Matsumo T, Murohara T, Imaizumi T.
Deparment of Internal Medicine III, Kurume University School of Medicine, Japan.
OBJECTIVES: We studied whether External Counterpulsation (ECP) improves myocardial ischemia, exercise tolerance and cardiac function in patients with coronary artery disease (CAD).
BACKGROUND: External Counterpulsation lowers angina and raises exercise tolerance in patients with CAD. Some objective improvements of ischemia by ECP have been reported, but they should be confirmed further. Less documented have been the detailed effects of hemodynamics.
METHODS: External Counterpulsation was performed for a total of 35 h in patients with stable CAD (n=12) who showed evidence of exercise-induced myocardial ischemia despite conventional medical or surgical therapies. All patients had significant stenotic lesions in major coronary arteries.
RESULTS: External Counterpulsation improved all exercise test parameters (p<0.05): exercise duration, time to 1-mm ST segment depression, rate-pressure product at peak exercise and rate-pressure product at 1-mm ST segment depression. More important was the prevalence of exercise-induced reversible perfusion defects by thallium scintigraphy decreased after treatment (p<0.01). External Counterpulsation did not change systolic function but improved diastolic filling, left ventricular (LV) end-diastolic pressure (p<0.05) by cardiac catheterization and LV peak filling rate end-diastolic volume/s (p<0.05) by radionuclide scintigraphy. These hemodynamic improvements were related to decreased plasma brain natriuretic peptides levels after ECP (p<0.05).
CONCLUSIONS: Thus, ECP treatment reduced myocardial ischemia by thallium scintigraphy in association with improved LV diastolic filling in patients with stable CAD and improves exercise tolerance.
Mayo Clin Proc 2000 Sep;75(9):961-5
Noninvasive revascularization by enhanced external counterpulsation: a case study and literature review.
Singh M, Holmes DR Jr, Tajik AJ, Barsness GW.
Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, Minn 55905, USA.
Close to 8 million people in the United States suffer from symptoms of coronary artery disease (CAD). Regrettably, the population of patients with ischemic coronary diseases is not readily amenable to surgical or percutaneous revascularization continues to grow. Patients who are not candidates for standard revascularization procedures and in whom aggressive medical therapy fails to control symptoms, External Counterpulsation (ECP) is an innovative, noninvasive outpatient treatment to advance quality of life by decreasing ischemic symptoms and permit increased activity. We report the case of a 56 year-old woman with severe, symptomatic CAD receiving maximal medical therapy who underwent a course of ECP therapy because she was not a good candidate for other forms of revascularization. The patient showed improvement in her anginal symptoms and complete resolution of myocardial ischemia on repeat nuclear stress imaging. This case suggests that ECP is a safe and effective method of reducing symptoms of myocardial ischemia in patients for whom standard percutaneous or surgical revascularization is not suitable.
Clin Cardiol 2000 Apr;23(4):254-8
Long-term prognosis of patients with angina treated with enhanced external counterpulsation: five-year follow-up study.
Lawson WE, Hui JC, Cohn PF.
Division of Cardiology, SUNY at Stony Brook 11794, USA.
BACKGROUND: External Counterpulsation (ECP) is a noninvasive treatment for coronary artery disease (CAD) that has been used successfully in patients not responding to medical and/or surgical therapy.
HYPOTHESIS: The study was undertaken to assess the effect of EECP on long-term prognosis in such patients.
METHODS: Major adverse cardiovascular events (MACE) were tracked in 33 patients with CAD treated with ECP. Patients were subgrouped based on whether or not they demonstrated an early improvement in radionuclide stress perfusion imaging (Responders vs. Nonresponders) and followed for MACE over a mean follow-up of 5 years. Patient population characteristics included 73% with multivessel disease; 45% with prior myocardial infarction(s); and 61% who had undergone either coronary artery bypass grafting (CABG) or percutaneous transluminal coronary angioplasty (PTCA), or both.
RESULTS: There were 26 of 33 (79%) Responders, and 7 of 33 (21%) Nonresponders. Subsequent MACE over the 5-year follow-up included four deaths and eight patients with cardiovascular events [acute myocardial infarct (4), new CABG or PTCA (6), valve replacement (1), unstable angina (1)]. Nonresponders had significantly (p<0.01) more MACE (6/7 or 86%) than Responders (6/26 or 23%). On the whole, 21 or the 33 (64%) patients stayed alive and without MACE and the need for revascularization 5 years post ECP treatment.
CONCLUSION: This study proposes that for most patients who show improvement in radionuclide stress perfusion post treatment, ECP may be a successful, lasting therapy.
Cardiology 2000;94(1):31-5
Treatment benefit in the enhanced external counterpulsation consortium.
Lawson WE, Hui JC, Lang G.
Division of Cardiology and Department of Surgery, SUNY at Stony Brook, NY, USA. wlawson@ts.uh.sunysb.edu
The percent study used a cohort of 2,289 consecutive patients enrolled in the External Counterpulsation (ECP) Consortium to assess whether results of university studies showing ECP safety and effectiveness in treating angina can be generalized. ECP was well endured and found to be safe with a 4.0% rate of adverse experiences. Angina class improved in 74% of patients with limiting angina (Canadian Cardiovascular Society, CCS, functional class II-IV), with patients most impaired at baseline demonstrating the greatest improvement (39.5% of patients in CCS III and IV improved 2 or more classes). Efficacy was not dependent of provider setting or experience, women responded as well as men, and even though younger patients demonstrated a greater likelihood of improvement, ECP was effective in patients ranging from 19 to 97 years. These findings may indicate extending ECP treatments to a broader range of patients.
Heart Dis 1999 Sep-Oct;1(4):221-5
External counterpulsation for the treatment of myocardial ischemia.
Cohn PF.
State University of New York Health Sciences Center at Stony Brook, Stony Brook, New York 11794-8171, USA.
External Counterpulsation (ECP) is a procedure that uses three sets of cuffs to squeeze the vascular beds of the leg and thigh in sequential manner timed to the patient’s electrocardiogram (ECG). Results of nonrandomized studies performed at the State University of New York Health Sciences Center at Stony Brook and a multicenter randomized study performed at seven centers throughout the United States indicate that the procedure has beneficial hemodynamic and clinical effects in selected patients with chronic angina that is refractory to standard medical and surgical therapy.
External Counterpulsation improved myocardial perfusion and coronary flow reverse in patients with chronic stable angina; evaluation by (13)N- ammonia positron emission tomography.
Masuda D, Nohara R, Hirai T, Kataoka K, Chen LG, Hosokawa R, Inubushi M, Tadamura E, Fujita M, Sasayama S.
Department of Cardiovascular Medicine, Graduate School Medicine, Kyote University, Japan.
AIMS: The mechanisms by which external counterpulsation therapy exerts its beneficial effects on chronic and symptomatic stable angina is largely unknown. To clarify the mechanism of action of external counterpulsation, we used (13)N-ammonia positron emission tomography to evaluate myocardial perfusion.
METHODS and RESULTS: This was not a randomized controlled study. Eleven patients (eight male, age 61.6+/9.7) with angina pectoris underwent external counterpulsation therapy for 35 1 hour sessions. They underwent a treadmill exercise test and (13)N-ammonia positron emission tomography, both at rests and with dipyridamole, before and after external counterpulsation therapy. Neurohumoral factors and nitric oxide were also evaluated. Myocardial perfusion increased at rest after therapy (0.69+/-0.27 to 0.85+/-0.47 ml x min (-1) x g(-1), P<0.05). In ischemic regions, particularly the anterior region, myocardial perfusion at rest and with dipyridamole and coronary flow reserve improved significantly after therapy (at rest: 0.71+/-0.26 to 0.86+/-0.31; P<0.05, with dipyridamole: 1.26+/-0.65 to 1.84+/-0.94; P<0.02, coronary flow reserve: 1.75+/-0.24 to 2.08+/-0.28; P<0.04). Exercise time was prolonged and the time to 1-mm ST depression improved markedly (P<0.01). After therapy, nitric oxide levels increased (P<0.02) and neurohumoral factors decreased.
CONCLUSIONS: External Counterpulsation therapy improved myocardial perfusion at rest with dipyridamole and was associated with an increased exercise tolerance with (13)N-ammonia positron emission tomography and increased nitric oxide levels. These results suggest that one of the external counterpulsation mechanisms is development and recruitment of collateral vessels. Copyright 2001. The European Society of Cardiology.
PMID: 11482918 [PubMed-indexed for MEDLINE]
Comparison of patients undergoing enhanced external counterpulsation and percutaneous coronary interventions for stable angina pectoris.
Holubkov R, Kennard ED, Foris JM, Kelsey SF, Soran O, Williams DO, Holmes DR.
Department of Epidemiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
External Counterpulsation (ECP) has recently emerged as a treatment options for angina in selected patients suitable for revascularization with percutaneous coronary intervention (PCI). We compared baseline characteristics and 1- year outcome in 2 cohorts of PCI candidates presenting with stable symptoms: 323 patients treated with ECP in the International EECP Patient Registry (IEPR), and 448 NHLBI Dynamics Registry patients treated with elective PCI. Compared with patients receiving PCI, IEPR patients had a higher prevalence of many risk factors including prior PCI (53.0% vs 33.3%, p<0.001), prior coronary artery bypass grafting (42.1% vs 18.6%, p<0.001), prior myocardial infarction (56.4% vs 27.8%, p<0.001), history of congestive heart failure (16.8% vs 9.2%, p<0.01), and history of diabetes (37.9% vs 23.5%, p<0.001). Left ventricular ejection fraction was lower among IEPR patients (mean 50.3% vs 59.2%, p<0.001). At 1 year, survival was comparable in the 2 cohorts (98.7% IEPR vs 96.8% PCI, p=NS), as were rates of coronary artery bypass grafting during follow-up (4.5% IEPR vs 5.7% PCI, p=NS). At 1 year, 43.7% of IEPR patients reported no anginal symptoms compared with 73.4% of Dynamic Registry patients (p<0.001). Rates of severe symptoms (Canadian Cardiovascular Society class III, IV, or unstable) at 1 year were 15.5% among IEPR patients and 9.5% in the Dynamic Registry (p=0.02). PCI candidates suitable for and treated with ECP had 1 year major events rates comparable to patients receiving elective PCI. Although PCI was associated with substantially lower rates of 1 year symptoms, ECP may be a safe treatment option for selected patients with obstructive coronary disease.
