New graduated pressure regimen for external counterpulsation reduces mortality and improves outcomes in congestive heart failure: a report from the Cardiomedics External Counterpulsation Patient Registry.

External counterpulsation (ECP) has been shown to increase exercise tolerance and reduce angina episodes, Canadian Cardiovascular Society Functional (CCSF) class, anginal medication usage, and hospitalizations in refractive CCSF class III and IV stable angina. However, the high pressures and resulting 1.5:1-2:1 peak diastolic to peak systolic pressure (D/S) ratios shown to be optimal in the treatment of angina can cause excessive preload and adverse effects in congestive heart failure (CHF) patients, particularly those with left ventricular ejection fractions <40%. Data were retrospectively analyzed from the Cardiomedics ECP Registry on 127 New York Heart Association (NYHA) class II-IV CHF patients (79.6% men; average age +/- SD, 68.2+/-15.6 years), with a comorbidity of CCSF class III-IV refractive angina, who were serially treated with 35 hours of ECP (1 h/d, 5 d/wk for 7 weeks) at unconventionally low pressures and D/S ratios under a new graduated pressure regimen. The pressures and D/S ratios were gradually increased in stages over the 7-week ECP regimen. The patients were divided into three groups based on the pressures applied and the resulting average D/S ratios (Low, Mid, and High). In the Low D/S ratio group (average D/S ratio 0.7:1), all-cause mortality in the year following ECP treatment was only 1.85% (one of 54 patients), whereas over the same time period in the Mid D/S ratio group (average D/S ratio 1.08:1), all-cause mortality was 7.69% (three of 39 patients) and in the High D/S ratio group (average D/S ratio 1.32:1), all-cause mortality was 8.82% (three of 34 patients). For the Low, Mid, and High D/S ratio groups, respectively: 1) average left ventricular ejection fractions increased 23.0%, 20.1%, and 17.5%; 2) NYHA class declined 36.6%, 29.6%, and 29.6%; and 3) all-cause hospitalizations, including terminal admissions, were reduced 85.7%, 82.6%, and 57.1% in the year following ECP therapy from the prior year. There were no adverse effects or withdrawals from the ECP therapy and no significant difference in sex-based outcomes. Consequently, ECP applied at low pressures and average D/S ratios of 0.7:1 under the new graduated pressure regimen is safe and effective in the treatment of CHF and produces a significant reduction in mortality, compared with the 8.5% annualized mortality of the Multicenter Automatic Defibrillator Implantation Trial II (MADIT II) (N=1232) of NYHA class II-III CHF and the 12.2% annual mortality of the Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure (COMPANION) study (N=595) of NYHA class III-IV CHF. Lower pressures improve patient comfort and may encourage more CHF patients to seek treatment. The reduction in hospitalizations should significantly reduce the cost of treating CHF.