Enhanced External Counterpulsation Treatment Research Articles

Analysis of baseline factors associated with reduction in chest pain in patients with angina pectoris treated by enhanced external counterpulsation

Data from the International Enhanced External Counterpulsation (EECP) Patient Registry were analyzed to determine which patient characteristics influence improvement in angina class with EECP treatment. Patients with severely disabling angina at baseline, men, and those without a history of smoking are more likely to improve their angina class after EECP, whereas those with diabetes mellitus, prior bypass surgery, and heart failure were less likely to benefit.

A review of enhanced external counterpulsation clinical trials.

A variety of clinical trials of enhanced external counterpulsation (EECP) have been conducted since the 1960s. The vast majority of these studies have investigated the use of EECP in patients with angina pectoris. Only one of these trials was randomized. These clinical trials have demonstrated the benefits of EECP in terms of reduction in anginal episodes, increased exercise times, and improvement in health-related quality of life scores. The International EECP Patient Registry, through its phase I and II enrollment, is expanding the data set on outcomes after EECP treatment.

Current use of enhanced external counterpulsation and patient selection.

Most patients who receive enhanced external counterpulsation (EECP) have symptomatic coronary artery disease. These patients have either responded poorly to pharmacologic therapy or are poor candidates for revascularization procedures. Such patients receive a variety of consistent benefits from EECP treatment. As more is learned about EECP, patients once excluded from early clinical trials are now able to take advantage of EECP. Nevertheless, EECP is not suitable for some patients. It has a favorable adverse event profile for most patients undergoing the treatment. Medicare reimbursement coverage limitations remain an obstacle to having a broad cross-section of patients benefit from EECP.

Relation of the pattern of diastolic augmentation during a course of enhanced external counterpulsation (EECP) to clinical benefit (from the International EECP Patient Registry [IEPR

E external counterpulsation (EECP) is a noninvasive counterpulsation technique that reduces angina and extends time to exercise-induced ischemia in patients with symptomatic stable angina. In addition to relieving myocardial ischemia, EECP is associated with improved quality of life. It uses a sequential inflation of 3 sets of pneumatic cuffs wrapped around the lower extremities. The cuffs are inflated sequentially at the onset of diastole, producing aortic counterpulsation, diastolic augmentation (DA), and increased venous return. At the onset of systole, external pressure in the cuffs is released, producing a decrease in systolic pressure (systolic unloading). These hemodynamic effects are monitored noninvasively by assessing the finger plethysmographic waveforms. A typical course of EECP involves 1 to 2 hours/day for a total of 35 hours of therapy. It has been hypothesized that the sustained benefits of EECP result from effective DA, which promotes coronary collateral formation or recruitment. A previous study has demonstrated that patients who are younger, male, nonsmoking, and without multivessel coronary or noncardiac vascular disease are most likely to have higher DA at the end of an EECP treatment course. Patients with higher DA ratios at the end of EECP tended to have a greater reduction in angina class than those with lower DA ratios, suggesting that clinical benefit from EECP is associated with the magnitude of DA. That initial study was limited by assessing the DA ratios on the final day of EECP therapy. This present analysis further investigates the role of DA in EECP by assessing the impact of DA levels both at the first and last treatment session with EECP.

Effects of enhanced external counterpulsation on stress radionuclide coronary perfusion and exercise capacity in chronic stable angina pectoris

Enhanced external counterpulsation (EECP) is an effective noninvasive treatment for patients with coronary artery disease (CAD). EECP has been demonstrated to improve anginal class and time to ST-segment depression during exercise stress testing. This study assesses the efficacy of EECP in improving stress-induced myocardial ischemia using radionuclide perfusion treadmill stress tests (RPSTs). The international study group enrolled patients from 7 centers with chronic stable angina pectoris and a baseline ischemic pre-EECP RPST. Patients’ demographic and clinical characteristics were recorded. A baseline pre-EECP maximal RPST was performed within 1 month before EECP treatment. The results were compared with a follow-up RPST performed within 6 months of completion of a 35-hour course of EECP. Four centers performed post-EECP RPST to the same level of exercise as pre-EECP, whereas 3 centers performed maximal RPST post-EECP. The study enrolled 175 patients (155 men and 20 women). Improvement in angina, defined by ≥1 Canadian Cardiovascular Society angina class change, was reported in 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-EECP vs 7.41 ± 2.03 minutes post-EECP, p <0.0001); 42 of the 78 patients (54%) in this group showed significant improvement in RPST perfusion images. Thus, EECP was effective in improving stress myocardial perfusion in patients with chronic stable angina at both comparable (baseline) and at maximal exercise levels.

Benefit and Safety of Enhanced External Counterpulsation in Treating Coronary Artery Disease Patients with a History of Congestive Heart Failure

Enhanced external counterpulsation (EECP) is used to noninvasively treat refractory angina patients, including those with a history of heart failure. The International EECP Patient Registry was used to examine the benefit and safety of EECP treatment, including a 6-month follow-up, in 1,957 patients, 548 with a history of heart failure. The heart failure cohort was older, with more females, a greater duration of coronary artery disease, more prior infarcts and revascularizations. Significantly fewer heart failure patients completed the course of EECP, and exacerbation of heart failure was more frequent, though overall major adverse cardiac events (MACE, i.e. death, myocardial infarction, revascularization) during treatment were not significantly different. The angina class improved in 68%, with comparable quality of life benefit, in the heart failure cohort. At 6 months, patients with congestive heart failure maintained their reduction in angina but were significantly more likely to have experienced a MACE end point.

Does higher diastolic augmentation predict clinical benefit from enhanced external counterpulsation?: Data from the international EECP patient registry (IEPR)

Enhanced external counterpulsation (EECP) has been demonstrated to be an effective treatment for stable angina in patients with coronary disease. The hemodynamic effects of EECP are maximized when the ratio of diastolic to systolic pressure area is in the range of 1.5 to 2.0. It is hypothesized that patients undergoing EECP who are able to achieve higher diastolic augmentation (DA) ratios may derive greater clinical benefit. This study examines the relationship between the DA ratio and clinical outcomes in patients undergoing EECP. We analyzed demographic, noninvasive hemodynamic, and clinical outcome data on 1,004 patients enrolled in the International EECP Patient Registry (IEPR) for treatment of chronic angina between January 1998 and August 1999. Blood pressure waveforms were recorded from finger plethysmography. Six-month clinical outcomes were obtained by telephone interview. At the end of EECP treatment, 370 (37%) patients had a higher DA ratio (defined as > or = 1.5) and 634 (63%) had a lower DA ratio (defined as < 1.5). Factors associated with a lower DA ratio included age > or =65 years (p <0.001), female gender (p < 0.001), left ventricular ejection fraction < 35% (p < 0.05), hypertension (p < 0.01), prior coronary bypass surgery (p < 0.01), noncardiac vascular disease (p < 0.001), multivessel disease (p < 0.01), congestive heart failure (p < 0.01), current smoking (p < 0.01), unsuitability for further revascularization (p < 0.001), and higher baseline angina class (p < 0.001). There were no significant differences regarding diabetes mellitus, prior coronary angioplasty, prior myocardial infarction, or antianginal medication use between patients with higher or lower DA ratios. Based on a multiple logistic regression model, independent predictors of a DA ratio < 1.5 at the end of EECP included current smoking (odds ratio 3.3; 95% confidence intervals 2.0-5.4); multivessel disease (1.7; 1.3-2.3); female gender (2.2; 1.7-3.0); no prior EECP (1.9; 1.1-3.3); noncardiac vascular disease (2.3; 1.7-2.9); age > or = 65 years (1.7; 1.4-2.2), and patients not suitable for revascularization (1.6; 1.2-2.0). By the end of therapy, there were no significant differences in myocardial infarction, revascularization rates, or nitroglycerin use with respect to higher DA ratios. At 6-month follow-up, patients with higher DA had a trend toward a greater reduction in angina class compared with those with lower DA (p = 0.069). There was a significantly higher rate of unstable angina and congestive heart failure in the group not achieving higher augmentation (p < 0.05). Patients who are younger, male, nonsmoking, and without multivessel coronary or noncardiac vascular disease are most likely to have higher DA with EECP. Patients with higher DA tended to have a greater reduction in angina class at 6-month follow-up compared with those with lower DA ratios. There is evidence that higher DA ratios are associated with improved short- or long-term clinical outcomes, suggesting that clinical benefit from EECP is associated with the magnitude of DA.

Enhanced external counterpulsation improves exercise tolerance, reduces exercise-induced myocardial ischemia and improves left ventricular diastolic filling in patients with coronary artery disease

OBJECTIVESWe examined whether enhanced external counterpulsation (EECP) improves myocardial ischemia, exercise tolerance and cardiac function in patients with coronary artery disease (CAD).BACKGROUNDEnhanced external counterpulsation reduces angina and improves exercise tolerance in patients with CAD. Some objective improvements of ischemia by EECP have been reported, but they should be confirmed further. Detailed hemodynamic effects of EECP have been less well documented.METHODSEnhanced 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.RESULTSEnhanced 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. Moreover, the prevalence of exercise-induced reversible perfusion defects by thallium scintigraphy decreased after treatment (p < 0.01). Enhanced external counterpulsation did not alter 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 < 0.01) and time to peak filling rate (p < 0.05) by radionuclide scintigraphy. These hemodynamic improvements were associated with decreased plasma brain natriuretic peptides levels after EECP (p < 0.05).CONCLUSIONSThus, EECP treatment improves exercise tolerance and reduced myocardial ischemia by thallium scintigraphy in association with improved LV diastolic filling in patients with stable CAD.

Treatment Benefit in the Enhanced External Counterpulsation Consortium

The present study utilized a cohort of 2,289 consecutive patients enrolled in the Enhanced External Counterpulsation (EECP) Consortium to evaluate whether results of university studies showing EECP safety and effectiveness in treating angina can be generalized. EECP was found to be safe and well tolerated 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 independent of provider setting or experience, women responded as well as men, and although younger patients demonstrated a greater likelihood of improvement, EECP was effective in patients ranging from 19 to 97 years. Extending the benefit of EECP treatment to a wider range of patients may be indicated based on these findings.

Enhanced External Counterpulsation as a New Treatment Modality for Patients with Erectile Dysfunction

Enhanced external counterpulsation (EECP) is a noninvasive treatment modality which can increase arterial blood flow in peripheral and coronary arterial disease. Several studies have demonstrated an increase in the flow of the internal iliacal artery and in carotid and renal perfusion during EECP treatment. We investigated the effect of EECP in patients with erectile dysfunction (ED). Thirteen patients were treated with EECP for 20 days, 1 h per day. Patients reported a significant improvement of penile rigidity after completion of the EECP treatment and a significant improvement of penile peak systolic flow was measured by Doppler sonography. No adverse effects were observed. In conclusion, EECP seems to be an effective treatment modality in patients with ED.

Enhanced External Counterpulsation in the Treatment and Rehabilitation of Coronary Patients in Indonesia

We report our experience using the new noninvasive treatment for coronary patients called enhanced external counterpulsation (EECP). Thallium-201 stress scintigraphy and treadmill test were done before and after 36 sessions of EECP treatment on 38 coronary patients. The results showed significant (P &lt; 0.01) improvement in perfusion as well as exercise tolerance in 86.8% and 94.2% of patients, respectively. The symptoms of angina pectoris and functional classes of the patients also showed significant (P &lt; 0.05) improvement. All patients tolerated the treatment without serious complications. The magnitude and rate of increased exercise tolerance achieved by EECP treatment was greater than those achieved by training after coronary bypass surgery (CABG) or exercise training rehabilitation program for the matched coronary patients reported by others 7 , 8 . The mean double products (DP) from the treadmill test results of the improved Tl-201 perfusion subgroups decreased significantly (P &lt; 0.001). On the contrary, the DP of the unimproved subgroup increased significantly (P &lt; 0.001). This could mean improvement in efficiency of the heart in the former, that is, more work was done with lower pressure-pulse products.

Efficacy of enhanced external counterpulsation in the treatment of angina pectoris

Eighteen patients with chronic angina despite surgical and medical therapy were treated with an improved system of enhanced external counterpulsation (EECP) (1 hour daily for a total of 36 hours). Patients underwent a baseline treadmill thallium-201 stress test. After EECP treatment, a thallium stress test was repeated for the same exercise duration. One week after treatment, patients also underwent a maximal stress test. All patients improved in anginal symptoms and generally decreased antianginal medications, with 16 obtaining complete relief from angina. Pre- and post-thallium stress testing performed for the same duration showed complete resolution of ischemic defects in 12 patients (67%), reduction in the area of ischemia in 2 (11%), and no change in 4 (22%). Thus, a decrease in myocardial ischemia was observed in 14 patients (78%; p < 0.01). The exercise duration of maximal stress testing after EECP significantly improved from 8.14 ± 0.71 to 9.72 ± 0.77 minutes (p < 0.005), although the double product did not change significantly. Analysis of these 2 tests in the subgroup of 14 patients with improvement in thallium studies showed significant increases in both exercise duration (8.58 ± 0.66 to 10.44 ± O.59 minutes; p < 0.001) and double product (21,827 ± 2,044 to 24,842 ± 1,707 mm Hg · beats/min; p < 0.01). The improvement in reperfusion defects and increase in exercise duration are reflections of improved perfusion to ischemic regions of the myocardium. EECP uses additional thigh balloons and sequenced balloon inflation, effecting a significant increase in diastolic augmentation over previously available methods. It appears to be a safe and effective therapy for selected patients with chronic angina.