Primer: practical approach to the selection of patients for and application of EECP.

Over the past decade, the frequency of use of enhanced external counterpulsation (EECP) has increased in patients with angina, irrespective of medical therapy and coronary revascularization status. Many patients referred for EECP have one or more comorbidities that could affect this treatment's efficacy, safety, or both. By use of data from more than 8,000 patients enrolled in the International EECP Patient Registry, we provide practical guidelines for the selection and treatment of patients. We have focused on considerations for patients who have one or more of the following characteristics: age older than 75 years, diabetes, obesity, heart failure, and peripheral vascular disease. We have also reviewed outcomes and treatment recommendations for individuals with poor diastolic augmentation during treatment, for those with atrial fibrillation or pacemakers, and for those receiving anticoagulation therapy. Lastly, we examined relevant data regarding extended courses of EECP, repeat therapy, or both. While clinical studies have demonstrated the usefulness of EECP in selected patients, these guidelines permit recommendations for the extended application of this important treatment to subsets of patients excluded from clinical trials.

Effect of enhanced external counterpulsation on resting oxygen uptake in patients having previous coronary revascularization and in healthy volunteers.

This study analyzed the acute effects of enhanced external counterpulsation (EECP) on oxygen uptake (VO2) at rest in adults with symptomatic coronary artery disease (CAD) compared with healthy volunteers. EECP therapy increases exercise tolerance in patients with refractory angina pectoris. This may be attributed, at least in part, to a training effect, but measurement of VO2 during an EECP treatment session has not been previously reported. We measured VO2 continuously in 20 adults during a single treatment session of EECP, including 10 subjects with previous coronary revascularization who were referred for EECP therapy for refractory angina, and 10 healthy, sedentary volunteers. VO2 was measured for 10 minutes before EECP, during a 30-minute EECP treatment session, and for 10 minutes after cessation of EECP treatment. Patients with CAD were older (65.9 +/- 12 vs 38.5 +/- 7 years, p = 0.002) and had a higher body mass index (32.0 +/- 10.0 vs 25.5 +/- 3.0 kg/m2, p = 0.027) and percent body fat (37 +/- 7% vs 21+/-9%, p = 0.006). VO2 at rest, although slightly lower in the CAD group, was not significantly different (2.75 +/- 0.54 vs 3.19 +/- 0.51 ml/kg/min, p = 0.09). The 2 groups demonstrated a small, sustained increase in VO2 during EECP treatment (CAD +0.66 +/- 0.56 ml/kg/min, p < 0.005; healthy +0.72 +/- 0.40 ml/kg/min, p < 0.001; CAD vs healthy, p = 0.13), which returned to baseline levels during recovery. In conclusion, VO2 at rest is increased to the same degree during an EECP treatment session in healthy subjects and symptomatic patients with CAD. This effect may contribute to the increased exercise tolerance of patients with refractory angina after receiving EECP therapy.

Outcome of ventricular fibrillation developing during percutaneous coronary interventions in 19,497 patients without cardiogenic shock.

Ventricular fibrillation (VF) developing out of hospital or even in hospital has a reported prognosis for survival that is <50%. We examined the prognosis for VF in 19,497 patients undergoing percutaneous coronary intervention and identified 164 who had VF (0.84%). The time to defibrillation was <1 minute and was successful in all without sequelae. Thus, VF developing in the catheterization laboratory is unique in terms of prognosis.

Abbreviated dosing of N-acetylcysteine prevents contrast-induced nephropathy after elective and urgent coronary angiography and intervention.

BACKGROUND AND HYPOTHESIS: Several studies have utilized low-dose regimens of N-acetylcysteine (NAC) for 48 hours to prevent contrast-induced nephropathy (CIN) after cardiac catheterization (cath) and percutaneous coronary intervention (PCI). A lengthy pretreatment period with NAC may not be feasible in urgent situations. The purpose of this study was to assess the efficacy of an abbreviated, higher dose regimen of NAC for the prevention of CIN after elective and urgent coronary angiography (cath) and/or percutaneous coronary intervention (PCI). METHODS: We prospectively evaluated 80 patients referred for elective or urgent cath and/or PCI with stable chronic renal insufficiency (creatinine clearance <50 cc/min). Patients were randomized to: NAC 1000 mg PO 1 hour before cath/PCI and 4 hours later, or placebo. All patients received hydration (0.9% saline) before and after cath/PCI (minimum total volume > or = 1500 mL). CIN was defined as an increase of Cr > or = 0.5 mg/dL or > or = 25% 48 hours after cath/PCI. RESULTS: CIN occurred in 3 of 36 (8%) patients of the NAC group vs. 11 of 44 (25%) in the placebo group (P = 0.051; OR 3.7, 95% CI 0.94-14.4). Serum creatinine (mean +/- SD) remained stable in the NAC group after cath/PCI (2.02 +/- 0.56 vs. 2.10 +/- 0.81 mg/dL; P = 0.34), but increased after cath/PCI in the placebo group (1.93 +/- 0.53 vs. 2.10 +/- 0.74 mg/dL; P < 0.01). CONCLUSIONS: An abbreviated, higher dose regimen of NAC prevents the rise of serum creatinine 48 hours after cath/PCI, and may prevent CIN after cath/PCI.

Predicting mortality in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention (PAMI risk score).

We performed a pooled analysis of the Primary Angioplasty in Myocardial Infarction (PAMI) trials to examine predictors of death after primary percutaneous coronary intervention. Using these data, we developed a risk score with a range of 0 to 15 points. The PAMI risk score was found to be a strong predictor of late mortality.