Daniel B. Sims

Human immunodeficiency virus infection and left ventricular assist devices: a case series.

Historically, advanced heart failure therapies were considered inappropriate for patients infected with human immunodeficiency virus (HIV). As HIV has become a chronic illness with the advent of highly active anti-retroviral therapy (HAART), cardiac transplantation has been used for selected HIV patients with end-stage heart failure. We present a case series describing the clinical outcomes with left ventricular assist device (LVAD) use in 4 patients with HIV. Three of the patients are alive: 1 after a successful bridge to transplant and the other 2 on continued device support at 18 and 13 months after implantation. No infectious complications occurred in 3 patients, and no opportunistic infections occurred in the fourth patient. De novo allosensitization did not occur in our patients after LVAD implantation. With the ongoing donor shortage, implantation of an LVAD in advanced heart failure patients with HIV with controlled viremia on HAART represents a viable option.

Twelve hours of sustained ventricular fibrillation supported by a continuous-flow left ventricular assist device.

Left ventricular assist device (LVAD) therapy improves survival and quality of life by mechanically unloading the left ventricle and maintaining hemodynamics in patients with end‐stage heart failure. LVADs can also be lifesaving by maintaining hemodynamics during ventricular arrhythmia. Continuous‐flow LVADs have become the preferred LVAD technology. As presented here, a continuous‐flow LVAD successfully provided hemodynamic support to a patient in sustained ventricular fibrillation for over 12 hours when the internal defibrillator was unable to terminate the arrhythmia. This case demonstrates that continuous‐flow LVADs can be lifesaving in the setting of otherwise certain hemodynamic collapse from sustained ventricular fibrillation. (PACE 2012; 35:e144–e148)

Rate responsive pacing using cardiac resynchronization therapy in patients with chronotropic incompetence and chronic heart failure

AIMS Chronotropic incompetence (CI) is a common finding in patients with advanced chronic heart failure (CHF) and is associated with a worse functional capacity. Whether rate responsive pacing with cardiac resynchronization therapy (CRT) would acutely improve exercise performance in patients with advanced CHF and severe CI (<70% age-predicted maximum heart rate) is unknown. METHODS AND RESULTS Patients (n = 13) with CHF, a CRT device, and severe CI were randomized in a double-blind crossover pilot study to either DDD (control) or DDDR (rate responsive) pacing. Six minutes walk test (6MWT) distance, oxygen consumption at anaerobic threshold (VO(2) @ AT), and maximal oxygen consumption (VO(2) max) were measured. One week later, testing was repeated in the alternate pacing mode. Rate responsive pacing commenced with standard settings in only 9 of 13 (69%) patients. In these 9 subjects, 6MWT distance improved acutely from 358.5 ± 40.7 to 376.8 ± 24.5 m with DDDR pacing (P< 0.05). VO(2) max did not improve with DDDR pacing (14.0 ± 3.2 mL/kg/min) compared with DDD pacing (13.9 ± 3.0 mL/kg/min; P= 0.69). VO(2) @ AT tended towards improvement with DDDR pacing (10.8 ± 2.9 mL/kg/min) compared with DDD pacing (9.6 ± 1.8 mL/kg/min; P= 0.29). There was a linear relationship between the increase in heart rate at minute 3 during rate responsive pacing and improvement in VO(2) @ AT (r = 0.83, P< 0.05). CONCLUSION When rate responsive pacing using a CRT device is achieved in patients with advanced CHF and severe CI, parameters of aerobic exercise performance improve acutely. Routine exercise testing to ensure successful restoration of heart rate response may be beneficial to optimize CRT settings in this patient population.

Ventricular assist device support as a bridge to heart transplantation in patients with giant cell myocarditis

Giant cell myocarditis (GCM) carries a poor prognosis and many patients require end‐stage therapies. This study sought to determine the outcome of patients bridged with ventricular assist devices (VAD) to orthotopic heart transplantation (OHT).

Frailty Assessment in Advanced Heart Failure

BACKGROUND Several studies have recently demonstrated the value of frailty assessment in a general heart failure (HF) population; however, it is unknown whether these findings are also applicable in advanced HF. We investigated the utility of frailty assessment and its prognostic value in elderly patients with advanced HF. METHODS Forty consecutive elderly subjects aged ≥65 years, with left ventricular ejection fraction ≤35%, New York Heart Association class III or IV, and a 6-minute walk test <300 m were enrolled from the HF clinic at Montefiore Medical Center between October 2012 and July 2013. Subjects were assessed for frailty with the Fried Frailty Index, consisting of 5 components: hand grip strength, 15-foot walk time, weight loss, physical activity, and exhaustion. All subjects were prospectively followed for death or hospitalization. RESULTS At baseline, the mean age of the cohort was 74.9 ± 6.5 years, 58% female, left ventricular ejection fraction 25.6 ± 6.4%, 6-minute walk test 195.8 ± 74.3 m and length of follow-up 454 ± 186 days. Thirty-five percent were prefrail and 65% were frail. Frailty status was associated with the combined primary endpoint of mortality and all-cause hospitalization (hazard ratio [HR] 1.93, 95% confidence interval [CI] 1.15-3.25, P = .013). On individual analysis, frailty was associated with all-cause hospitalizations (HR 1.92, 95% CI 1.12-3.27, P = .017) and non-HF hospitalizations (HR 3.31, 95% CI 1.14- 9.6, P = .028), but was not associated with HF hospitalizations alone (HR 1.31, 95% CI 0.68-2.49, P = .380). CONCLUSIONS Frailty assessment in patients with advanced HF is feasible and provides prognostic value. These findings warrant validation in a larger cohort.

Therapeutic hypothermia in ST elevation myocardial infarction: a systematic review and meta-analysis of randomised control trials

Objective Our objective is to gain a better understanding of the efficacy and safety of therapeutic hypothermia (TH) in patients with acute ST elevation myocardial infarction (STEMI) through an analysis of randomised controlled trials (RCTs). Background Several RCTs have suggested a positive outcome with the use of TH in the prevention of myocardial injury in the setting of an acute STEMI. However, there are currently no clinical trials that have conclusively shown any significant benefit. Methods Electronic databases were used to identify RCTs of TH in the patient population with STEMI. The primary efficacy end point was major adverse cardiovascular event (MACE). Secondary efficacy end points included all-cause mortality, infarct size, new myocardial infarction and heart failure/pulmonary oedema (HF/PO). All-bleeding, ventricular arrhythmias and bradycardias were recorded as the safety end points. Results Six RCTs were included in this meta-analysis, enrolling a total of 819 patients. There was no significant benefit from TH in preventing MACE (OR, 01.04; 95% CI 0.37 to 2.89), all-cause mortality (OR, 1.48; 95% CI 0.68 to 3.19), new myocardial infarction (OR, 0.99; 95% CI 0.20 to 4.94), HF/PO (OR, 0.52; 95% CI 0.15 to 1.77) or infarct size (standard difference of the mean (SDM), −0.1; 95% CI −0.23 to 0.04). However, a significant reduction of infarct size was observed with TH utilisation in anterior wall myocardial infarction (SDM, −0.23; 95% CI −0.45 to −0.02). There was no significant difference seen for the safety end points all-bleeding (OR 1.32; 95% CI 0.77 to 2.24), ventricular arrhythmias (OR, 0.85; 95% CI 0.54 to 1.36) or bradycardias (OR, 1.16; 95% CI 0.74 to 1.83). Conclusions Although TH appears to be safe in patients with STEMI, meta-analysis of published RCTs indicates that benefit is limited to reduction of infarct size in patients with anterior wall involvement with no demonstrable effect on all-cause mortality, recurrent myocardial infarction or HF/PO.

Watchful Waiting in Continuous-Flow Left Ventricular Assist Device Patients With Ongoing Hemolysis Is Associated With an Increased Risk for Cerebrovascular Accident or Death

Background—Management of hemolysis in the setting of suspected device thrombosis in continuous-flow left ventricular assist device patients varies widely, ranging from watchful waiting with intensified antithrombotic therapy to early surgical device exchange. The aim of this study was to compare the outcomes of hemolysis events treated with surgical interventions versus medical management alone. Methods and Results—A retrospective review of Heartmate II continuous-flow left ventricular assist device patients at 2 centers from January 2009 to September 2014 was completed. Patients were categorized as surgical management if hemolysis refractory to intensification of standard antithrombotic therapy was treated surgically. The primary end point was the first occurrence of cerebrovascular accident (CVA) or death. Sixty-four hemolysis events occurred in 49/367 patients implanted with Heartmate II continuous-flow left ventricular assist devices. Of 49 primary hemolysis events, 24 were treated with surgical interventions. After surgical treatment, 1 patient died and 2 experienced CVAs, as compared with 3 deaths and 9 CVAs in the 25 patients who remained on intensified antithrombotic therapy alone. The 1-year freedom from CVA or death was 87.5% and 49.5% in the surgical and medical cohorts, respectively (P=0.027). Resolution of a primary hemolysis event without CVA or death occurred in 21/24 patients treated with surgical interventions and in 13/25 who remained on medical therapy alone. A similar association between treatment and outcome was noted in the 15 recurrent hemolysis events. Conclusions—Hemolysis refractory to intensification of antithrombotic therapy identifies continuous-flow left ventricular assist device patients at major risk for CVA and death. Early device exchange should be considered to minimize these risks.

Effect of β-Blocker Cessation on Chronotropic Incompetence and Exercise Tolerance in Patients With Advanced Heart Failure

Background—Chronotropic incompetence is defined as the inability to reach 80% of heart rate (HR) reserve or 80% of the maximally predicted HR during exercise. The presence of chronotropic incompetence is associated with reduced peak oxygen consumption, and rate–responsive pacing therapy is under investigation to improve exercise capacity in heart failure (HF). However, uncertainty exists about whether chronotropic incompetence and reduced exercise tolerance in HF are attributable to &bgr;-blockade. Methods and Results—Subjects with HF and receiving long-term &bgr;-blocker therapy underwent cardiopulmonary exercise tolerance testing under 2 conditions in random sequence: (1) after a 27-hour washout period (Off-BB) and (2) 3 hours after &bgr;-blocker ingestion (On-BB). Norepinephrine levels were drawn at rest and at peak exercise. &bgr;1-response to norepinephrine was assessed using the chronotropic responsiveness index: &Dgr;HR/&Dgr;log norepinephrine. Nineteen patients with systolic HF (left ventricular ejection fraction, 22.8±7.7%) were enrolled. Mean age was 49.4±12.3 years. Average carvedilol equivalent dose was 29.1±17.0 mg daily. Peak HR off/on &bgr;-blockers was 62.7±18.7% and 51.4±18.2% HR reserve (P<0.01) and 79.1±11.0% and 70.3±12.3% maximally predicted HR (P<0.01). For the Off-BB and On-BB conditions, the respiratory exchange ratios were 1.05±0.06 and 1.05±0.10 (P=0.77), respectively, confirming maximal and near identical effort in both conditions. The peak oxygen consumption was 16.6±3.34 and 15.9±3.31 mL/kg/min (P=0.03), and the chronotropic responsiveness index was 19.3±7.2 and 16.2±7.1 (P=0.18). Conclusions—Acute &bgr;-blocker cessation does not normalize the chronotropic response to exercise in patients with advanced HF and chronotropic incompetence.

Bridging cardiogenic shock patients with short-term ventricular support at a community hospital to long-term ventricular support at a tertiary hospital

BACKGROUND Patients in cardiogenic shock require immediate circulatory support. Outcomes of patients who underwent short-term ventricular assist device (STVAD) implantation in a community hospital (CH) as a bridge to a long-term VAD (LTVAD) were compared with those who received both implants at the same tertiary hospital (TH). METHODS Data were retrospectively reviewed for patients with a STVAD who were bridged to a LTVAD in a TH from 1997 to 2010. We studied outcomes and survival censored for cardiac transplantation. RESULTS Thirty-seven patients (73% male) were identified. Mean age was 52 ± 16 years, 30% were diabetic, and 65% had intra-aortic balloon pump support. Reasons for STVAD implantation were an acute myocardial infarction, 38%; post-cardiotomy, 38%, decompensated chronic heart failure, 19%; and others, 5%. A STVAD was implanted in a CH in 20 patients (54%), and they had fewer cardiovascular risk factors than those whose STVAD was implanted at the TH. All patients at the CH were at Interagency Registry for Mechanically Assisted Circulatory Support 1 compared with 71% at the TH (p = 0.014). Patients from the CH tended to die sooner after LTVAD implant, although long-term survival was similar. At the 1-year follow-up, 65% from the CH were alive or had received a transplant vs 60% from the TH. CONCLUSION Patients with cardiogenic shock in whom a STVAD was implanted in a CH and then were bridged to a LTVAD in a TH had similar long-term survival as those bridged to LTVAD at the TH.

Antiplatelet Therapy and Adverse Hematologic Events During Heart Mate II Support

Background—Hematologic adverse events are common during continuous flow left ventricular assist device support; yet, their relation to antiplatelet therapy, including aspirin (ASA) dosing, is uncertain. Methods and Results—A single-center retrospective review of all patients supported by a continuous flow left ventricular assist device (Heart Mate II) from June 2006 to November 2014 was conducted. Patients were categorized into 3 groups: (1) ASA 81 mg+dipyridamole 75 mg daily (n=26) with a target international normalized ratio (INR) of 2 to 3 from June 2006 to August 2009; (2) ASA 81 mg daily (n=18) from September 2009 to August 2011 with a target INR of 1.5 to 2; and (3) ASA 325 mg daily from September 2011 to November 2014 with a target INR of 2 to 3 (n=70). Hemorrhagic and thrombotic outcomes were retrieved ⩽365 days after implantation. Cumulative survival free from adverse events was calculated using Kaplan–Meier curves and Cox proportional hazard ratios were generated. Hemorrhagic events occurred in 6 patients on ASA 81 mg+dipyridamole (26%; 0.42 events per patient year; mean INR at event, 2.2), 4 patients on ASA 81 mg (22%; 0.38 events per patient year; mean INR at event, 2.0), and in 38 patients on ASA 325 mg (54%; 1.4 events per patient year; mean INR at event, 2.2); P=0.004. Patients on ASA 325 mg had a higher adjusted hazard ratio of 2.9 (95% confidence interval, 1.2–7.0 versus ASA 81 mg+dipyridamole; P=0.02) and 3.4 (95% confidence interval, 1.2–9.5 versus ASA 81 mg; P=0.02) for hemorrhagic events. Thrombotic events rates were not different between groups. Conclusions—High-dose ASA in Heart Mate II patients treated concomitantly with warfarin is associated with an increased hazard of bleeding but does not reduce thrombotic events.