High Risk Of Right Ventricular Failure Research Articles

Temporary Right Ventricular Support Using the Existing Bypass Circuit During LVAD Implantation

BackgroundRight-sided heart failure after left ventricular assist device (LVAD) implantation carries high morbidity. We sought to develop a technique for expedient short-term right ventricular (RV) support with the cardiopulmonary bypass (CPB) circuit already in use during the LVAD implantation procedure. MethodsPatients at high risk for RV failure during LVAD implantation were supported by a modified CPB circuit. A standard CPB circuit was modified to include a series of 4 wye (Y) bridge connections, allowing the ability to exclude the venous reservoir and oxygenator and to flow venous blood or arterialized blood in the same CPB outflow line. ResultsFrom 2019 to 2022 at a single institution, 6 patients were identified as high risk for early RV failure. Preoperative mean clinical values included central venous pressure of 16.3 ± 3.2 mm Hg, pulmonary capillary wedge pressure of 26.7 ± 3.2 mm Hg, tricuspid annular plane systolic excursion of 1.2 ± 0.23 cm, RV stroke work index of 311.7 ± 32.5, and central venous pressure/pulmonary capillary wedge pressure of 0.61 ± 0.10. All 6 patients were successfully weaned from CPB to LVAD support without the need for RV support at the conclusion of the implantation procedure. ConclusionsWe describe a configuration that supports the right ventricle during the critical period after CPB when it is at high risk of failure while the patient is being resuscitated with transfusions and volume. This technique provides flexibility in the management of complex, critically ill patients with RV failure, increasing the possibility of intraoperative RV recovery and successful separation from CPB during LVAD implantation.

Pulmonary Vasodilator Response of Combined Inhaled Epoprostenol and Inhaled Milrinone in Cardiac Surgical Patients.

Pulmonary hypertension (PH) and right ventricular (RV) dysfunction are major complications in cardiac surgery. Intraoperative management of patients at high risk of RV failure should aim to reduce RV afterload and optimize RV filling pressures, while avoiding systemic hypotension, to facilitate weaning from cardiopulmonary bypass (CPB). Inhaled epoprostenol and inhaled milrinone (iE&iM) administered in combination before CPB may represent an effective strategy to facilitate separation from CPB and reduce requirements for intravenous inotropes during cardiac surgery. Our primary objective was to report the rate of positive pulmonary vasodilator response to iE&iM and, second, how it relates to perioperative outcomes in cardiac surgery. This is a retrospective cohort study of consecutive patients with PH or RV dysfunction undergoing on-pump cardiac surgery at the Montreal Heart Institute from July 2013 to December 2018 (n = 128). iE&iM treatment was administered using an ultrasonic mesh nebulizer before the initiation of CPB. Demographic and baseline clinical data, as well as hemodynamic, intraoperative, and echocardiographic data, were collected using electronic records. An increase of 20% in the mean arterial pressure (MAP) to mean pulmonary artery pressure (MPAP) ratio was used to indicate a positive response to iE&iM. In this cohort, 77.3% of patients were responders to iE&iM treatment. Baseline systolic pulmonary artery pressure (SPAP) (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.24-2.16 per 5 mm Hg; P = .0006) was found to be a predictor of pulmonary vasodilator response, while a European System for Cardiac Operative Risk Evaluation (EuroSCORE II) score >6.5% was a predictor of nonresponse to treatment (≤6.5% vs >6.5% [reference]: OR, 5.19; 95% CI, 1.84-14.66; P = .002). Severity of PH was associated with a positive response to treatment, where a higher proportion of responders had MPAP values >30 mm Hg (42.4% responders vs 24.1% nonresponders; P = .0237) and SPAP values >55 mm Hg (17.2% vs 3.4%; P = .0037). Easier separation from CPB was also associated with response to iE&iM treatment (69.7% vs 58.6%; P = .0181). A higher proportion of nonresponders had a very difficult separation from CPB and required intravenous inotropic drug support compared to responders, for whom easy separation from CPB was more frequent. Use of intravenous inotropes after CPB was lower in responders to treatment (8.1% vs 27.6%; P = .0052). A positive pulmonary vasodilator response to treatment with a combination of iE&iM before initiation of CPB was observed in 77% of patients. Higher baseline SPAP was an independent predictor of pulmonary vasodilator response, while EuroSCORE II >6.5% was a predictor of nonresponse to treatment.

Heart-lung interactions in COVID-19: prognostic impact and usefulness of bedside echocardiography for monitoring of the right ventricle involvement.

Due to the SARS-CoV-2 infection–related severe pulmonary tissue damages associated with a relative specific widespread thrombotic microangiopathy, the pathophysiologic role of heart–lung interactions becomes crucial for the development and progression of right ventricular (RV) dysfunction. The high resistance in the pulmonary circulation, as a result of small vessel thrombosis and hypoxemia, is the major cause of right heart failure associated with a particularly high mortality in severe COVID-19. Timely identification of patients at high risk for RV failure, optimization of mechanical ventilation to limit its adverse effects on RV preload and afterload, avoidance of medication-related increase in the pulmonary vascular resistance, and the use of extracorporeal membrane oxygenation in refractory respiratory failure with hemodynamic instability, before RV failure develops, can improve patient survival. Since it was confirmed that the right-sided heart is particularly involved in the clinical deterioration of patients with COVID-19 and pressure overload-induced RV dysfunction plays a key role for patient outcome, transthoracic echocardiography (TTE) received increasing attention. Limited TTE focused on the right heart appears highly useful in hospitalized COVID-19 patients and particularly beneficial for monitoring of critically ill patients. In addition to detection of right-sided heart dilation and RV dysfunction, it enables assessment of RV-pulmonary arterial coupling and evaluation of RV adaptability to pressure loading which facilitate useful prognostic statements to be made. The increased use of bedside TTE focused on the right heart could facilitate more personalized management and treatment of hospitalized patients and can contribute towards reducing the high mortality associated with SARS-CoV-2 infection.

Predicting Significant Right Ventricular Failure Post-LVAD Implantation Using CMR Compared to Echocardiography and Right Heart Catheterisation

Purpose Right ventricular failure (RVF) complicates 10-40% of LVAD implants. Significant RVF is associated with increased mortality and reduced chance of being bridged to transplant. It is therefore crucial to identify patients at high risk of RVF using pre-operative investigations. We investigated markers of RV function on pre-LVAD echocardiography (echo), right heart catheterization (RHC) and cardiovascular magnetic resonance imaging (CMR) in predicting significant post-LVAD RVF. Methods We performed a single centre retrospective analysis of 220 patients who underwent LVAD implantation between 2011-18. 33 patients had CMR within 15 months pre-LVAD implantation. CMR was used to derive RV volumes, TAPSE, RV ejection fraction, strain and scar burden. RV function parameters were derived from echo and RHC just prior the LVAD implantation. INTERMACS criteria was used to categorize RVF based on duration of pharmaceutical support (post-implant IV inotropes/vasodilators/inhaled nitrous oxide) - mild ( 14 days). The latter also included the need for RVAD or death due to RVF. Moderate and severe RVF were considered as significant RVF. Results The median age was 49 (IQR 39-56). 31 were males. 18 patients had no/mild RVF; 14 had significant RVF (8 moderate RVF, 6 severe RVF); 1 patient was not categorised due to incomplete data. 29 survived to discharge. Dilated cardiomyopathy was the commonest aetiology of heart failure (17/33) followed by ischaemic heart disease (11/33). Echo derived pulmonary hypertension (42 vs 36mmHg) and proportion of those with tricuspid regurgitation (83.3% vs 92.8%) were not different in the two groups. PVR on RHC was not different between the groups (2.82 vs 3.68 WU). CMR derived volumes, TAPSE (12.2 vs 12.1mm), Global longitudinal strain (-9.1% vs -7.2%) and radial strain (-12.4% vs -10.0%) and the presence of scar were not different between the two groups. CMR-RVEF however was lower in the group significant RVF (23.5 ± 8.2%) when compared to the group with no/mild RVF (31.0 ± 10.7%) (p=0.03). Conclusion When compared to indices from RHC and echo, pre-operative RVEF on CMR is the only marker that differentiated the group who developed significant post-LVAD RVF from the group that did not. A larger study with CMR closer to the time of LVAD implant is needed to validate this.

Safety of Mechanical Circulatory Support for Left Ventricular Non-Compaction: Single Center Experience

Purpose Left ventricular non-compaction (LVNC) can present with congestive heart failure and thromboembolic events. Thrombus formation in the left ventricle from LVNC is commonly seen and has resulted in a very cautionary approach for mechanical circulatory support (MCS) for heart failure presentation. Due to continued limitations in availability for donor heart options other than MCS therapy remain limited. The aim of this single center study is to assess freedom from pump thrombosis at 6 months in LVNC. Methods Retrospective analysis of 18 patients (out of 244) who met the diagnostic criteria for LVNC underwent an LVAD implantation. Primary endpoint for this study was freedom from pump thrombosis at 6 months. Secondary outcomes were to assess in-hospital mortality, 30-day mortality and incidence of right ventricular failure after LVAD implantation. Pre-operative variables including laboratory, 2-D Echo, and right heath catheterization findings were comparable (Table 1). Results 11 out of 18 patients (61.11%) were males and 11 (61.11 %) were African Americans. 1 (5.56%) patient had pump thrombosis and underwent a successful pump exchange. Freedom from pump thrombosis at 6 months was 94.44% (17/18). 30-day survival was 100 % and 6-month survival was 88.89 % (16/18). Right ventricular failure (RVF) was noted in 9 patients (50%), even though pre-operative RV function analyses did not identify these patients as high risk for RVF (PAPi 3.56 (CI 95% 2.22-4.89), TAPSE 2.01 (CI 95% 1.80-2.23), S-PRIME 10.35 (CI 95% 7.80-12.89)). RVF was defined as requirement of inotropic support for > 4 weeks or placement of a temporary right ventricular assist device. Conclusion LVAD therapy for patients with LVNC is a very safe option with low incidence of pump thrombosis, 30 days and in-hospital mortality; however, a much higher rate of RVF is observed in this cohort when compared with INTERMACS registry data for patients with other diagnosis of cardiomyopathies undergoing MCS therapy.

Limitations of Preoperative Right Ventricular Failure Assessment in Patients Undergoing LVAD Insertion

Purpose Early right ventricular (RV) failure after LVAD is associated with increased morbidity and mortality. Several hemodynamic indices have been suggested to identify patients at risk for RV failure, however their predictive value remains unclear. Methods We retrospectively identified patients at our center who required mechanical RV support following LVAD between 2007-2018, with either surgical (Centrimag RVAD) or percutaneous (Impella RP, Protek Duo) devices. Those receiving RVAD at time of LVAD insertion were excluded. Predictors of RV failure were calculated with preoperative hemodynamics, including RA/PCWP (low risk (LR) 0.64), PAPI (LR >2, medium risk (MR) 1.5-2, HR 600 mmHg*mL/m2, MR 300-600, HR 5.5), and EUROMACS-RHF (LR 4). Results 37 patients required mechanical RV support. 18 received percutaneous RVAD and 19 surgical RVAD. Figure 1 summarizes the proportion of patients who would have been identified as low, medium, or high risk of RV failure. Mean RA/PCWP was 0.43 ± 0.19, with 13.5% of patients identified as high risk. 70.3% of patients had PAPI suggestive of low risk, with only 10.8% and 18.9% identified as medium or high risk, respectively. RVSWI identified 51.3% of patients as medium risk of RV failure and 21.6% as high risk, with mean 519 ± 316 mmHg*mL/m2. EUROMACS-RHF classified 51.3% as medium risk and 22% as high risk, while the RVFRS identified the majority of patients as low risk (83.8%). Conclusion Among patients who ultimately required mechanical support for RV failure following LVAD insertion, the majority would not have been identified as at risk using most currently available preoperative risk assessments. RVSWI and EUROMACS-RHF best predicted RV failure, identifying the majority of patients as at medium risk. In patients not identified as at risk preoperatively, easily deployed RV support may be an important means to rapidly address RV failure after LVAD insertion.

Temporary Right Ventricular Support in Left Vetricular Assist Device Recipients

Objectives: Right ventricular failure (RVF) remains a major early postoperative complication after left ventricular assist device (LVAD) placement despite attempts to identify patients (pts) at risk. We describe our experience with temporary right ventricular assist device (RVAD) support with CentriMag (Levitronix LLC, Waltham, MA) after LVAD placement. Methods: Between 01/2008 and 06/2011, 45 LVAD recipients (8 f; age 53.4±9.1, range: 25-70 years) with preoperative evidence of moderate to severe RVF (Pennsylvania University score >50 and Michigan University score >5) received a temporary CentriMag RVAD at our institutions. Etiology of cardiomyopathy was: idiopathic (n=24, 53%), ischemic (n=14, 31%) and valvular (n=7, 16%). In 34 pts the RVAD was inserted simultaneously with LVAD placement (primary) and in 11 others within 48 hours after LVAD placement (secondary). Results: During daily echocardiographic examinations a progressive improvement of RV function was documented in 29 (64.4%) pts (n=24, primary placement; n=5, secondary pl.). After an average of 12.1 postoperative days (POD) weaning from RVAD was carried out by reducing the flow by 10% every 12 h and after 16.2 POD it was successfully removed. All pts had RVEF of 38-40%, CVP of 10-15 mmHg and stable LVAD flow. RVAD removal was performed by a minimally invasive approach without re-sternotomy in 10 pts. Three (6.6%) pts required permanent support with an implantable centrifugal RVAD (HeartWare Inc., Miramar, FL). Ten (22.2%) pts died on temporary RVAD support. Overall 26 (57.7%) pts were discharged home (n=25, permanent LVAD support; n=1, permanent BVAD support) and 3 (6.6%) received successful heart transplantation. Conclusions: Implantation of an LVAD in pts with high risk for RVF is a feasible and effective therapy option if RV function is closely monitored. Once RVF is identified, immediate temporary RVAD placement improves the outcome. Weaning from and removal of the RVAD support allows pts to be on LVAD support only, thus providing good quality of life and enabling long-term mechanical support.

Right-to-left ventricular end-diastolic diameter ratio and prediction of right ventricular failure with continuous-flow left ventricular assist devices

Left ventricular assist device (LVAD) implantation is an accepted therapy for patients with end-stage heart failure. Post-operative right ventricular failure (RVF) still remains a major cause of morbidity and mortality in these patients. This study sought to identify echocardiography parameters to select patients with high risk of RVF after LVAD implantation. Prospectively collected pre-operative transesophageal echocardiography (TEE) and clinical data were evaluated in patients pre-selected for isolated LVAD or biventricular assist device (BiVAD) implantation. According to prevalence of RVF during the first post-operative 48 hours, patients were divided into those who developed RVF (isolated LVAD with RVF) and those who did not (isolated LVAD without RVF). Echocardiographic parameters for RV geometry, RV function, LV geometry, and the RV-to-LV end-diastolic diameter ratio (R/L ratio) were evaluated. For identification of the optimal cutoff of R/L ratio, receiver operating characteristics curves were constructed. An isolated LVAD was implanted in 115 patients and BiVAD in 22 patients. RVF developed in 15 patients (13%) after isolated LVAD implantation. The R/L ratio was markedly increased in the isolated LVAD with RVF and BiVAD groups compared with the isolated LVAD without RVF group. According to the receiving operating curve, the cutoff for the R/L ratio to predict RVF was 0.72. The odds ratio that RVF will develop is 11.4 in patients with an R/L ratio >0.72 (p = 0.0001). Increased R/L ratio successfully identifies patients with high risk of RVF after isolated LVAD implantation. Beyond standard measurements of RV function, the consideration of R/L ratio may be useful to improve risk stratification in patients before isolated LVAD implantation.

Successful Conversion of TandemHeart Left Ventricular Assist Device to Right Ventricular Assist Device After Implantation of a HeartMate XVE

A 60-year-old man with end-stage ischemic cardiomyopathy (ejection fraction, 10%) was admitted in cardiogenic shock, which was unresponsive to maximum inotropes and an intraaortic balloon pump. The TandemHeart (TH) left ventricular assist device (Cardiac Assist Inc, Pittsburgh, PA) was placed in the standard percutaneous transseptal configuration with improved hemodynamics. The HeartMate XVE (Thoratec Corp, Pleasanton, CA) implantation was performed as a bridge to transplant 5 days after TandemHeart insertion. The TandemHeart was converted to a temporary right ventricular assist device during the HeartMate XVE (Thoratec Corp) implantation due to right ventricular failure. The right ventricular assist device was weaned 3 days later. This strategy was useful, technically easy, and cost effective.