Readmissions after implantation of axial flow left ventricular assist device.

OBJECTIVES: The purpose of this study was to determine the occurrence and causes of readmissions after implantation of axial flow left ventricular assist device (LVAD). BACKGROUND: Based on the REMATCH (Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure) study experience, readmissions after LVAD implantation are thought to be frequent. METHODS: We retrospectively analyzed admissions to our facility in a cohort of 115 patients implanted between January 2008 and July 2011 with the HeartMate II axial flow LVAD, of whom 42 were bridged to transplant. To account for repeated events, Andersen-Gill models were used to determine possible predictors. RESULTS: The patients were followed for 1.4 ± 0.9 years. There were 224 readmissions in 83 patients. The overall readmission rate was 1.64 ± 1.97 per patient-year of follow-up. The readmission rate for the first 6 months was 2.0 ± 2.3 and decreased to 1.2 ± 2.1 during subsequent follow-up. Leading causes were bleeding (66 readmissions in 34 patients), mostly gastrointestinal bleed (51 in 27 patients), cardiac (51 in 36 patients, most for HF or arrhythmia), infections (32 in 25 patients) of which 6 were pump related, and thrombosis (20 in 15 patients) including 13 readmissions due to hemolysis. Preoperative variables associated with (fewer) readmissions in a multivariate model include residence within our hospital-extended referral zone of Minnesota and the neighboring states (hazard ratio: 0.66; 95% confidence interval: 0.48 to 0.91; p = 0.011), hemoglobin (hazard ratio: 0.91, 95% confidence interval: 0.84 to 0.99; p = 0.027) and N-terminal pro-B-type natriuretic peptide (hazard ratio: 0.98; 95% confidence interval: 0.96 to 1.0 per 1,000-unit increase, p = 0.022). C-statistic for the model: 0.63. CONCLUSIONS: Readmission rates after axial flow LVAD implantation decrease during the first 6 months and then stabilize. The leading causes are bleeding, cardiac (heart failure and arrhythmia), infections, and thrombosis.

Ethical analysis of withdrawing ventricular assist device support.

OBJECTIVE: To describe a series of patients with heart failure supported with a ventricular assist device (VAD) who requested (or whose surrogates requested) withdrawal of VAD support and the legal and ethical aspects pertaining to these requests. PATIENTS AND METHODS: We retrospectively reviewed the medical records of patients at Mayo Clinic, Rochester, MN, from March 1, 2003, through January 31, 2009, who requested (or whose surrogates requested) withdrawal of VAD support and for whom the requests were fulfilled. We then explored the legal and ethical permissibility of carrying out such requests. RESULTS: The median age of the 14 patients identified (13 men, 1 woman) was 57 years. Requests were made by 2 patients and 12 surrogates. None of the patients' available advance directives mentioned the VAD. For 11 patients, multidisciplinary care conferences were held before withdrawal of VAD support. Only 1 patient had an ethics consultation. All 14 patients died within 1 day of withdrawal of VAD support. CONCLUSION: Patients have the right to refuse or request the withdrawal of any unwanted treatment, and we argue that this right extends to VAD support. We also argue that the cause of death in these cases is the underlying heart disease, not assisted suicide or euthanasia. Therefore, patients with heart failure supported with VADs or their surrogates may request withdrawal of this treatment. In our view, carrying out such requests is permissible in accordance with the principles that apply to withdrawing other life-sustaining treatments.

Immediate and long-term hemodynamic and clinical effects of sildenafil in patients with pulmonary arterial hypertension receiving vasodilator therapy.

OBJECTIVE: To determine the immediate and long-term effects of adding sildenafil, a phosphodiesterase-5 inhibitor, to the medical regimen of patients with pulmonary arterial hypertension (PAH). PATIENTS AND METHODS: Thirteen patients with PAH received empirical adjunctive sildenafil treatment at the Mayo Clinic in Rochester, Minn, between November 1, 2000, and August 31, 2001. All received a 25-mg dose of sildenafil, increased by 25 mg at 8-hour intervals, if tolerated, up to 100 mg during hemodynamic monitoring for 24 to 48 hours. Long-term effects on right heart hemodynamics were assessed by noninvasive right ventricular systolic pressure, right ventricular index of myocardial performance, and a 6-minute walk test. RESULTS: Sildenafil significantly increased cardiac output (CO) (P = .04) and decreased pulmonary artery systolic pressure, mean pulmonary artery pressure, pulmonary vascular resistance, and mean arterial pressure (P < or = .01) at peak measurements (obtained 1-2 hours after highest dose). At trough measurements (obtained 8 hours after highest dose), sildenafil significantly decreased pulmonary artery systolic pressure, mean pulmonary artery pressure, and mean arterial pressure (P = .01). Ten patients discharged from the hospital were taking the highest-tolerated dose of sildenafil every 8 hours. The right ventricular systolic pressure and right index of myocardial performance showed no significant improvement at follow-up (117 +/- 70 days), although concomitant treatment with epoprostenol could be tapered in 2 patients. Changes in New York Heart Association classes were inconsistent, and improvements in the 6-minute walk test were not significant. CONCLUSION: Sildenafil has an immediate pulmonary vasodilator effect in patients already receiving vasodilators for PAH. Its long-term effects on right heart function and functional status are equivocal. A large, prospective, well-designed study is needed to determine the effects of sildenafil on PAH, both in untreated and concurrently treated patients.