Temporary Mechanical Circulatory Support During Bariatric Surgery: A Novel Bridge to Durable Left Ventricular Assist Device and Cardiac Transplantation.

Advanced heart failure (HF) with comorbid severe obesity presents a unique surgical dilemma: bariatric surgery may help patients meet cardiac transplantation body mass index (BMI) criteria, but poor cardiac function puts them at increased intraoperative risk. Per International Society for Heart and Lung Transplantation (ISHLT) guidelines BMI > 35 is a contraindication for orthotopic heart transplantation. Temporary mechanical circulatory support (MCS) with Impella 5.5 during bariatric surgery, as presented in this report, may help solve this dilemma for some patients. We present three patients with severe obesity and advanced heart failure (HF) who underwent successful bariatric surgery while supported by Impella 5.5 (Abiomed, Inc., Danvers, MA).

Efficacy of bariatric intervention as a bridge to cardiac transplant.

BACKGROUND: Many patients with heart failure (HF) are denied cardiac transplants due to inability to meet transplantation body mass index (BMI) criteria. Bariatric intervention, including surgery, medication, and weight loss guidance, may help patients lose weight and become eligible for transplantation. OBJECTIVE: We aim to contribute to the literature on the safety and efficacy of bariatric intervention on patients with obesity and HF who are awaiting cardiac transplantation. SETTING: University hospital, United States. METHODS: This was a mixed retrospective/prospective study. Eighteen patients with HF and BMI >35 kg/m2 were reviewed. Patients were divided based on whether they underwent bariatric surgery or nonsurgical intervention and whether they had left ventricular assist devices or other advanced heart failure therapy including inotropic support, guideline-directed medical therapy, and/or temporary mechanical circulatory support. Weight, BMI, and left ventricular ejection fraction (LVEF) were collected before bariatric intervention and 6 months after bariatric intervention. RESULTS: No patients were lost to follow-up. Bariatric surgery led to statistically significant decreases in weight and BMI when compared with nonsurgical patients. At 6 months after intervention, surgical patients lost an average of 18.6 kg and decreased their BMI by 6.4 kg/m2 while nonsurgical patients lost 1.9 kg and decreased their BMI by .7 kg/m2. After bariatric intervention, surgical patients had an average LVEF increase of 5.9% and nonsurgical patients had an average decrease of 5.9%, although these findings lacked statistical significance. CONCLUSION: Our study suggests that bariatric intervention among patients with HF and obesity is a safe and effective method of weight and BMI reduction.

Variability in Blood Pressure Assessment in Patients Supported with the HeartMate 3TM.

Targeted blood pressure (BP) control is a goal of left ventricular assist device medical management, but the interpretation of values obtained from noninvasive instruments is challenging. In the MOMENTUM 3 Continued Access Protocol, paired BP values in HeartMate 3 (HM3) patients were compared from arterial (A)-line and Doppler opening pressure (DOP) (319 readings in 261 patients) and A-line and automated cuff (281 readings in 247 patients). Pearson (R) correlations between A-line mean arterial (MAP) and systolic blood pressures (SBP) were compared with DOP and cuff measures according to the presence (>1 pulse in 5 seconds) or absence of a palpable radial pulse. There were only moderate correlations between A-line and noninvasive measurements of SBP (DOP R = 0.58; cuff R = 0.47) and MAP (DOP R = 0.48; cuff R = 0.37). DOP accuracy for MAP estimation, defined as the % of readings within ± 10 mmHg of A-line MAP, decreased from 80% to 33% for DOP ≤ 90 vs. >90 mmHg, and precision also diminished (mean absolute difference [MAD] increased from 6.3 ± 5.6 to 16.1 ± 11.4 mmHg). Across pulse pressures, cuff MAPs were within ±10 mmHg of A-line 62.9%-68.8% of measures and MADs were negligible. The presence of a palpable pulse reduced the accuracy and precision of the DOP-MAP estimation but did not impact cuff-MAP accuracy or precision. In summary, DOP may overestimate MAP in some patients on HM3 support. Simultaneous use of DOP and automated cuff and radial pulse may be needed to guide antihypertensive medication titration in outpatients on HM3 support.

Monitoring cell-mediated immunity during immunosuppression reduction in heart transplant recipients with severe systemic infections.

BACKGROUND: Treatment for severe systemic infections in heart transplantation is reduction in immunosuppression while treating the infection. An assay that measures adenosine triphosphate production in activated lymphocytes (ImmuKnow® ) objectively monitors cellular immunity of transplant recipients. In this study, we used ImmuKnow® to adjust immunosuppression in heart transplant recipients with severe systemic infections. METHODS: Heart transplant recipients were followed with ImmuKnow® at the time of biopsy and diagnosis of systemic infection. Patients who developed an infection were monitored by ImmuKnow® assay with adjustments in immunosuppression based upon the results of the assay. Maintenance immunosuppression was reinstituted when the ImmuKnow® increased to >225 ng/mL of ATP. RESULTS: Two or more ImmuKnow® assays were performed in 80 patients. Thirteen patients developed severe systemic infections. ImmuKnow® mean value at the time of diagnosis of infection was 109 ± 49.2 ng/mL. Reduction in immunosuppression and treatment of infection resulted in normalization of ImmuKnow® level, resolution of infection, and no episodes of rebound rejection. CONCLUSION: Heart transplant recipients with severe systemic infections presented with a decreased ImmuKnow® , suggesting over immunosuppression. ImmuKnow® can be used as an objective measurement in withdrawing immunosuppression in heart transplant recipients with severe systemic infections.

Quality of life and functional capacity outcomes in the MOMENTUM 3 trial at 6 months: A call for new metrics for left ventricular assist device patients.

BACKGROUND: The Multicenter Study of MAGLEV Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 (MOMENTUM 3) clinical trial demonstrated improved 6-month event-free survival, but a detailed analysis of health-related quality of life (HR-QOL) and functional capacity (FC) was not presented. Further, the effect of early serious adverse events (SAEs) on these metrics and on the general ability to live well while supported with a left ventricular assist system (LVAS) warrants evaluation. METHODS: FC (New York Heart Association [NYHA] and 6-minute walk test [6MWT]) and HR-QOL (European Quality of Life [EQ-5D-5L] and the Kansas City Cardiomyopathy [KCCQ]) assessments were obtained at baseline and 6 months after HeartMate 3 (HM3, n = 151; Abbott, Abbott Park, IL) or HeartMate II (HMII, n = 138; Abbott) implant as part of the MOMENTUM 3 clinical trial. Metrics were compared between devices and in those with and without events. The proportion of patients "living well on an LVAS" at 6 months, defined as alive with satisfactory FC (NYHA I/II or 6MWT > 300 meters) and HR-QOL (overall KCCQ > 50), was evaluated. RESULTS: Although the median (25th-75th percentile) patient KCCQ (change for HM3: +28 [10-46]; HMII: +29 [9-48]) and EQ-5D-5L (change for HM3: -1 [-5 to 0]; HMII: -2 [-6 to 0]) scores improved from baseline to 6 months (p < 0.05), there were no differences between devices (p > 0.05). Likewise, there was an equivalent improvement in 6MWT distance at 6 months in HM3 (+94 [1-274] meters] and HMII (+188[43-340 meters]) from baseline. In patients with SAEs (n = 188), 6MWTs increased from baseline (p < 0.001), but gains for both devices were less than those without SAE (HM3: +74 [-9 to 183] meters with SAE vs +140 [35-329] meters without SAE; HMII: +177 [47-356] meters with SAE vs +192 [23-337] meters without SAE, both p < 0.003). SAEs did not affect the 6-month HR-QOL scores. The "living well" end point was achieved in 145 HM3 (63%) and 120 HMII (68%) patients (p = 0.44). CONCLUSIONS: Gains in HR-QOL and FC were similar early after HM3 and HMII implant. 6MWT improvements were attenuated in patients experiencing SAEs, but HR-QOL metrics did not change. The development of left ventricular assist device-specific HR-QOL tools is needed to better characterize the effect of SAEs on a patient's well-being. CLINICAL TRIAL NO: MOMENTUM 3 clinical trial #NCT02224755.

Clinical observations and outcome of ventricular tachycardia ablation in patients with left ventricular assist devices.

BACKGROUND: Ablation of ventricular tachycardia (VT) in patients with left ventricular assist devices (LVAD) is challenging and not well documented. This report describes our experience with endocardial VT ablation in six patients with an LVAD. METHODS: We retrospectively reviewed the clinical records of LVAD patients who underwent an ablation procedure for refractory VT. RESULTS: A total of eight ablation procedures were performed in six patients who, during the last 2 weeks before the ablation procedure, received a total of 101 appropriate shocks for VT. A closed aortic valve (n = 2) or aortic atheroma (n = 1) required a transseptal catheterization in three of six patients. The apical LVAD cannula served as a VT substrate in two of six patients. VT was eliminated in four patients and markedly reduced in two others. The latter two patients experienced a total of only four implantable cardioverter defibrillator (ICD) shocks during a follow-up of 130 and 493 days. Intravenous antiarrhythmic medications used in five of six patients before ablation were discontinued in all. The ablation procedures permitted hospital discharge in four of six patients. Five patients died during follow-up (228 ± 207 days after the procedure). The cause of death was unrelated to cardiac arrhythmias. One patient is still alive 1,205 days after the procedure. CONCLUSION: Ablation of VT in LVAD patients is feasible and can result in a markedly decreased VT burden with a reduction of ICD shocks. The subsequent discontinuation of intravenous antiarrhythmic medications may facilitate hospital discharge.

Ablation of left ventricular tachycardia via transeptal approach and crossing of a mechanical mitral valve prosthesis.

This report describes the clinical course of a patient with left ventricular assist device (LVAD) and refractory ventricular tachycardia (VT) who underwent successful left ventricular (LV) mapping and ablation complicated by the presence of a bioprosthetic aortic and a mechanical mitral valve. LV catheterization was achieved by crossing the mechanical valve. The patient remained hemodynamically stable during the procedure most likely as a result of LVAD support. There were no complications. A recurrence of monomorphic VT 2 months later required a second VT ablation procedure using the same transseptal-transmitral approach. The patient has since been free of implantable cardioverter defibrillator shocks for 2 months since the second procedure.

Elevated B-type natriuretic peptide without volume overload in a left ventricular assist device patient with a subdural hematoma.

We report a case of elevated B-type natriuretic peptide (BNP) without volume overload in a left ventricular assist device patient with a subdural hematoma and cerebral salt wasting syndrome suggesting a noncardiac etiology for BNP elevation.

Latency during left ventricular pacing from the lateral cardiac veins: a cause of ineffectual biventricular pacing.

We report three patients with cardiomyopathy and pronounced stimulus to QRS latency during left ventricular (LV) pacing from an epicardial cardiac vein. Delayed LV activation during simultaneous biventricular pacing produced an electrocardiographic pattern dominated by right ventricular stimulation. Hemodynamic parameters improved immediately after advancing LV stimulation (in one patient) or pacing the LV only (in two patients) coupled with dramatic improvement of heart failure symptoms.