Preoperative Right-Sided Cardiac Congestion Is Associated with Gastrointestinal Bleeding in Patients with Continuous-Flow Left Ventricular Assist Devices

Gastrointestinal bleeding in recipients of left ventricular assist devices-a systematic review

The twenty-first century has revolutionized the management of congestive heart failure with the widespread use of left ventricular assist devices and other treatment modalities that improve morbidity and mortality after the failure of medical management. These novel devices come with significant side effects. One of the most common side effects of left ventricular assist devices is the increased frequency of lower gastrointestinal bleeding compared to heart failure patients without left ventricular assist devices. Multiple etiologies of recurrent gastrointestinal bleeding in such patients have been studied. The decreased amount of von Willebrand factor polymers is now recognized as one of the most common causes of increased incidence of gastrointestinal bleeding in patients with left ventricular assist devices alongside increased arteriovenous malformations. Multiple treatment modalities have been identified to prevent and treat gastrointestinal bleeding in these patients. Since the use of left ventricular assist devices is becoming more prevalent in patients with advanced heart failure, we decided to conduct this systematic review. The article summarizes the incidence, pathophysiology, and management of lower gastrointestinal bleeding in patients with left ventricular assist devices.

Postimplant Phosphodiesterase-5 Inhibitor Use in Centrifugal Flow Left Ventricular Assist Devices

OBJECTIVES

This study examined the association between phosphodiesterase-5 inhibitor (PDE-5i) use and outcomes in patients with contemporary centrifugal flow left ventricular assist devices (LVADs).

BACKGROUND

PDE-5i use may affect outcomes in patients with continuous flow LVADs.

METHODS

Patients enrolled in INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support), with HeartMate 3 (n = 4,628) or HeartWare Ventricular Assist Device (HVAD) (n = 2,601) implant were included in the analysis. The mean duration of follow-up was 11.94 ± 8.65 months. PDE-5is were used in 2,173 patients. The primary endpoint was the composite of all-cause mortality, ischemic stroke, and pump thrombosis. Propensity matching and stabilized inverse probability of treatment weights were used to adjust for baseline differences between patients receiving and not receiving PDE-5i. Adjusted Cox proportional hazards analysis was performed for each outcome.

RESULTS

The primary endpoint was lower in the PDE-5i group (adjusted HR: 0.77; 95% CI: 0.69-0.86; P < 0.0001; HeartMate 3: adjusted HR: 0.77; 95% CI: 0.64-0.92; P = 0.0044; HVAD: adjusted HR: 0.76; 95% CI: 0.66-0.88; P = 0.0002). All-cause mortality was lower with PDE-5is (adjusted HR: 0.75; 95% CI: 0.65-0.86; P < 0.0001; HeartMate 3: adjusted HR: 0.70; 95% CI: 0.57-0.86; P = 0.0007; HVAD: adjusted HR: 0.78; 95% CI: 0.65-0.94; P = 0.0098) and fewer ischemic strokes with PDE-5is were observed (adjusted HR: 0.71; 95% CI: 0.56-0.89; P = 0.003; HeartMate 3: adjusted HR: 0.67; 95% CI: 0.45-0.99; P = 0.045; HVAD: adjusted HR: 0.73; 95% CI: 0.56-0.97; P = 0.03). LVAD thrombosis was unchanged with PDE-5is, with overall low event rates observed.

CONCLUSIONS

Postimplant PDE-5i use was associated with lower mortality and ischemic strokes in patients with centrifugal flow LVADs.

Preoperative Right Heart Dysfunction and Gastrointestinal Bleeding in Patients with Left Ventricular Assist Devices

Gastrointestinal bleeding (GIB) is a common cause of morbidity among patients supported by left ventricular assist devices (LVADs). The aim of this study was to identify if pre-LVAD right ventricular (RV) dysfunction is associated with risk of GIB after LVAD implantation. Of 398 patients implanted with LVADs between July 2008 and July 2016, 130 (33%) developed GIB at a median of 2.6 months following LVAD implantation. Arteriovenous malformations (AVMs) were found in 42 (34%) GIB patients. Patients with GIB were older and more likely to have hypertension, diabetes, and ischemic cardiomyopathy. On pre-LVAD echocardiography, GIB patients had increased RV diastolic dimension (4.7 ± 0.8 vs. 4.4 ± 0.9 cm, p = 0.02), a higher rate of greater than mild tricuspid valve (TV) regurgitation (73 [60%] vs. 120 [47%], p = 0.006), and underwent TV repair more often (38 [30%] vs. 43 [16%], p = 0.0006) during LVAD implantation. After multivariable adjustment, preoperative greater than mild RV enlargement (hazard ratio [HR] 2.32, 95% CI 1.12-5.03; p = 0.03), TV regurgitation (HR 1.83, CI 1.02-3.44; p = 0.01), and TV repair (HR 3.76, confidence interval [CI] 1.02-4.44; p = 0.01) remained associated with risk of GIB. This finding was driven by the AVM-GIB subgroup. Preoperative RV enlargement and TV regurgitation are associated with post-LVAD AVM-related GIB.

HeartWare Ventricular Assist Device Cannula Position and Hemocompatibility-Related Adverse Events

BACKGROUND

HeartWare ventricular assist device (HVAD) cannula position is associated with hemodynamics and heart failure readmissions. However, its impact on hemocompatibility-related adverse events (HRAEs) remains uncertain.

METHODS

HVAD patients were followed for 1 year after index hospitalization, when cannula coronal angle was quantified from chest x-ray film. Invasive right heart catheterization and transthoracic echocardiography were performed. One-year occurrences of each HRAE were compared between those with and without a cannula coronal angle of greater than 65 degrees.

RESULTS

Among 63 HVAD patients (median age 60 years, 63% male), 10 (16%) had a cannula coronal angle greater than 65 degrees. The wide-angle group had elevated intracardiac pressures and lower pulmonary artery pulsatility index (P < .05). They also had reduced right ventricular function by echocardiography. Freedom from HRAEs tended to be lower in the wide-angle group (24% vs 62%; P = .11). The rate of gastrointestinal bleeding was significantly higher in the greater than 65 degrees group (0.90 events/year vs 0.40 events/year; P = .013). The rates of stroke and pump thrombosis were statistically comparable irrespective of cannula angle (P > .05).

CONCLUSIONS

HVAD cannula coronal angle was associated with reduced right ventricular function and HRAEs. Prospective studies evaluating surgical techniques to ensure optimal device positioning and its effects on HRAEs are warranted.

Deep Y-Descent in Right Atrial Waveforms Following Left Ventricular Assist Device Implantation

BACKGROUND

Characterization of right heart catheterization (RHC) waveforms provides diagnostic and clinical information in heart failure patients. We aimed to investigate the implication of RHC waveforms, specifically the y-descent, in patients with left ventricular assist device (LVAD).

METHODS AND RESULTS

Patients underwent RHC and waveforms were quantified prior to and 6 months after LVAD implantation. The impact of a deep y-descent (>3 mmHg) on echocardiographic measures of right heart function and 1-year hemocompatibility-related adverse event rates were investigated. Eighty-nine patients (median 59 years old, 65 male) underwent RHC. RHC waveform showed unique changes following LVAD implantation, particularly an increase in the steepness of the y-descent. A post-LVAD deep y-descent was associated with reduced right ventricular function and enlarged right heart. Patients with post-LVAD deep y-descent had higher rates of gastrointestinal bleeding (0.866 vs 0.191 events/year) and stroke (0.199 vs 0 events/year) compared with those without (P< .05 for both).

CONCLUSION

RHC waveforms characterized by deep y-descent on RHC waveform during LVAD support was associated with impaired right ventricular function and worse clinical outcomes.

Hemodynamics of concomitant tricuspid valve procedures at LVAD implantation

BACKGROUND

Tricuspid regurgitation (TR) is common in patients receiving left ventricular assist device (LVAD) implantation. The current literature is conflicting regarding the effects of concomitant tricuspid valve repair (TVR) at LVAD implantation. We investigated the hemodynamic effects of concomitant TVR at LVAD implantation.

METHODS

Consecutive clinically stable LVAD outpatients who underwent hemodynamic ramp testings were enrolled in this study, and they were stratified by concomitant TVR. Results of hemodynamic ramp tests were compared between the TVR group and the non-TVR group.

RESULTS

Among 65 LVAD patients undergoing ramp tests, 34 patients had received TVR, and 31 had not. There were no significant differences in baseline characteristics between two groups except for higher degree of TR and lower pulmonary artery pulsatility index in the TVR group (P < .05 for both). Following LVAD implantation, the degree of TR improved significantly in the TVR group down to the comparable level with the non-TVR group. During ramp tests, the TVR group had steeper cardiac index slope (0.14 ± 0.12 vs 0.07 ± 0.07 L/min/m² /step, P = .002) and higher cardiac index at set LVAD speed (2.99 ± 0.84 vs 2.52 ± 0.42 L/min/m² , P = .007).

CONCLUSIONS

Concomitant TVR improves cardiac output and its response to LVAD speed change following LVAD implantation. Longitudinal clinical implications of such hemodynamic changes are unknown.

Optimal haemodynamics during left ventricular assist device support are associated with reduced haemocompatibility-related adverse events

AIMS

Left ventricular assist device (LVAD) therapy improves the haemodynamics of advanced heart failure patients. However, it is unknown whether haemodynamic optimization improves haemocompatibility-related adverse events (HRAEs). This study aimed to assess HRAEs in patients with optimized haemodynamics.

METHODS AND RESULTS

Eighty-three outpatients [aged 61 (53-67) years, 50 male] underwent a haemodynamic ramp test at 253 (95-652) days after LVAD implantation, and 51 (61%) had optimized haemodynamics (defined as central venous pressure < 12 mmHg, pulmonary artery wedge pressure < 18 mmHg, cardiac index > 2.2 L/min/m² ) following LVAD speed adjustment. One-year survival free of any HRAEs (non-surgical bleeding, thromboembolic event, pump thrombosis, or neurological event) was achieved in 75% of the optimized group and in 44% of the non-optimized group (hazard ratio 0.36, 95% confidence interval 0.18-0.73, P = 0.003). The net haemocompatibility score, using four escalating tiers of hierarchal severity to derive a total score for events, was significantly lower in the optimized group than the non-optimized group (1.02 vs. 2.00 points/patient; incidence rate ratio 0.51, 95% confidence interval 0.29-0.90, P = 0.021).

CONCLUSION

Left ventricular assist device patients in whom haemodynamics can be optimized had greater freedom from HRAEs compared to those without optimized haemodynamics.