P. Ozturk

Comparison of Continuous-Flow and Pulsatile-Flow Blood Pumps on Reducing Pulmonary Artery Pressure in Patients With Fixed Pulmonary Hypertension

Pulmonary hypertension (PH) is considered as a risk factor for morbidity and mortality in patients undergoing heart transplantation. Recently, left ventricular assist device (LVAD) implantation has been increasingly used in reducing pulmonary artery pressure (PAP) in patients with PH unresponsive to medical therapy. Herein, we aimed to compare the efficacy of continuous-flow and pulsatile-flow blood pumps on the improvement of PH in mechanical circulatory support patients. Twenty-seven patients with end-stage heart failure who underwent LVAD implantation surgery were enrolled. Fifteen of them (55.6%) had continuous-flow pump (HeartWare Ventricular Assist System, HeartWare, Inc., Miramar, FL, USA), and 12 of them (44.4%) had pulsatile pump (Berlin Heart EXCOR ventricular assist device, Berlin Heart AG, Berlin, Germany). The efficacy of LVADs on the improvement of PH was compared between continuous-flow and pulsatile pumps by the evaluation of systolic PAP, tricuspid annular plane systolic excursion (TAPSE), right ventricular systolic motion (RVSM), right ventricular ejection fraction (RVEF), and grade of tricuspid insufficiency (TI) for each of the study participants. All of the 15 patients who underwent continuous-flow blood pump implantation surgery (Group 1) were male with a mean age of 46.9 ± 11.7 years, and in pulsatile-flow blood pump implanted participants (Group 2), the mean age was 40.6 ± 16.8 years, all of whom were also male (P=0.259). Mean follow-up was 313.7 ± 241.3 days in Group 1 and 448.7 ± 120.7 days in Group 2 (P=0.139). In Group 1, mean preoperative and postoperative systolic PAP were measured as 51.7 ± 12.2 mm Hg and 22.2 ± 3.4 mm Hg, respectively, while those in Group 2 were 54.5 ± 7.5 mm Hg and 33.9 ± 6.4 mm Hg, respectively. A significantly greater decrease in systolic PAP was noticed in patients with continuous-flow blood pumps (P=0.023); however, no statistically significant difference was found when we considered the change in TAPSE between study groups (P=0.112). A statistical significance in the alteration of RVEF, RVSM, and the grade of TI during study visits was not found between the study groups (P=0.472, P=0.887, and P=0.237, respectively). Although the two studied types of LVADs were found to be effective in reducing PAP in heart transplantation candidates with PH, lesser postoperative systolic PAP values were achieved in patients who underwent continuous-flow pump implantation surgery.

Valvular procedures during ventricular assist device implantation.

BACKGROUND Increased experience and success with ventricular assist devices (VAD) has permitted more aggressive use in patients formerly believed to be inappropriate for mechanical circulatory support (MCS). There is no clearly proven policy to manage end-stage heart failure patients with valvular pathologies. The aim of this report was to analysis our experience with combined approach of VAD implantation and valvular procedures among patients with valvular heart disease and end-stage heart failure. METHODS We evaluated the clinical records of 67 patients who underwent MCS from April 2007 to September 2011. We identified 12 patients (17.9%) who received concomitant valvular procedures, four of whom had significant aortic insufficiency and received a simple coaptation stitch at the center to approximate the fibrous nodules of Arantius. The mechanical aortic valve was replaced with a stentless bioprosthesis in three patients. Mitral valve commissurotomy was performed in one patient with mitral stenosis and seven patients underwent tricuspit valve repair using an annuloplasty ring. RESULTS All 12 patients were males, of mean age 50.3 ± 11.5 years (range = 25-66). Eleven of them (91.6%) survived the early and late postoperative periods. Ten subjects (83.3%) continue to be supported with VAD; 1 (8.3%) was successfully bridged to transplantation. Each study participant regression of the valvular pathologies by early echocardiography demonstrated. CONCLUSION Concomitant valve surgery during VAD implantation appeared to be a reasonable option in end-stage heart failure patients with valvular heart disease.

New circulatory support system: heartware.

INTRODUCTION Through the new developments in medicine, heart failure therapy has advanced to mechanical circulatory support systems. The HeartWare Ventricular Assist System HVAD; HeartWare, Inc.; Miramar, Fla, USA) is a new device that is a centrifugal, intracorporeal, miniaturized and continuous flow pump that serves simple patient use and enhanced life quality. This article reports the midterm results of patients who underwent the heartware support system. MATERIALS AND METHODS We retrospectively compiled our data from December 2010, including 10 patients of mean age 51.8 years with 90% males, 70% of the overall patient cohort had dilated cardiomyopathy and remaining ones, ischemic disease. Mean left ventricular ejection fraction was 20.1% and mean systolic pulmonary artery pressure was 49.2 mm Hg. A single patient was grade 1; seven were grade 2; and remaining ones, grade 3 according to the INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) scale. All patients were operated with cardiopulmonary bypass (CPB) with moderate hypothermia. Tricuspid ring annuloplasty was performed in 3 (30%) patients. In one patient we removed a left ventricular thrombus. In a case with severe aortic regurgitation, we placed a simple coaptation stitch at the central portion of the three aortic cusps under the aortic cross clamp. The mean CPB duration was 95.5 minutes. RESULTS There was no operative or in-hospital mortality. Mean support time was 250.67 days. During the early postoperative period, one patient experienced a minor hemorrhagic neurological event also requiring a tracheostomy due to pneumonia. This patient has completely healed and on follow-up continues a normal life. All patients were asymptomatic regarding heart failure. One patient unfortunately died because of possible pancreatic cancer and sepsis. Two patients underwent transplantations on days 159 and 172 of support. CONCLUSION The HVAD system provided effective circulatory support for patients with end-stage heart failure with low adverse event rates. Long-term results are needed particularly for destination therapy candidates.

Right intra-atrial catheter placement for hemodialysis in patients with multiple venous failure

The purpose of this study is to evaluate the efficacy and safety of direct right atrial catheter insertion for hemodialysis in patients with multiple venous access failure. We retrospectively evaluated the charts of 27 patients with multiple venous access failure who had intra‐atrial dialysis catheter placement between October 2005 and October 2010 in our clinic. Permanent right atrial dialysis catheters were placed through a right anterior mini‐thoracotomy under intratracheal general anesthesia in all patients. Demographics of the cases, the patency rates of hemodialysis via atrial catheterization, existence of any catheter thrombosis, and catheter‐related infections were documented and used in statistical analysis. Seventeen women (63%) and 10 men (37%) with the mean age of 59.0 ± 7.1 years (47–71) were enrolled in this study. Chronic renal failure was diagnosed for the mean of 78.9 ± 24.3 months (33–130). Five patients (18.5%) died. Ventricular fibrillation and myocardial infarction were the causes of death in the early postoperative period in two patients. Two of the remaining three patients died because of cerebrovascular events, and one patient died because of an unknown cause. Ten patients (37%) had been using anticoagulate agents (warfarin) because of concomitant disorders such as deep vein thrombosis, operated valve disease, and arrhythmias. Catheter thrombosis and malfunction was determined in three cases (11.1%). Intra‐atrial hemodialysis catheterization is a safe and effective life‐saving measure for the patients with multiple venous failure and without any possibility of peritoneal dialysis or renal transplantation.

Left Ventricular Assist Device Implantation in Heart Failure Patients With a Left Ventricular Thrombus

BACKGROUND In this report, we share our experience with left ventricular assist device (LVAD) implantation in cases with a left ventricular (LV) thrombus. METHOD Over the 3 years, more than 100 end-stage heart failure cases have been treated with LVAD implantation in our center, including 6 patients with a LV thrombus. Three were detected using preoperative transthoracic echocardiography. Fifty percent of the patients had dilated cardiomyopathy and the remaining cases had an ischemic etiology. Double inotropic support with dopamine and dobutamine was used in all, with 3 drugs with the addition of adrenaline in 2 patients. In 4 cases we implanted the HeartWare Ventricular Assist System (HeartWare, Inc., Miramar, Fla, United States) and in the remaining 2 patients, the Berlin Heart EXCOR ventricular assist device (Berlin Heart AG, Berlin, Germany) for biventricular support. In 1 patient the apical ventriculotomy was extended to remove an intertrabecular thrombosis and ventricular septal surface covered with a dacron patch to minimize the thrombogenic potential. RESULTS Two patients died due to sepsis and multiorgan failure. None of the patients experienced a neurological event, pump thrombosis, or pump malfunction. Two subjects underwent re-explorations due to hemorrhage. Two candidates underwent successfull transplantation without any evidence of thrombosis in the explanted heart or device. CONCLUSION We believe that patients with a LV thrombus and preserved right ventricular function are good candidates for implantation of a LVAD after removing the intracavitary thrombus.

Fundus fluorescein angiographic findings in patients who underwent ventricular assist device implantation.

Disruption of microcirculation in various tissues as a result of deformed blood rheology due to ventricular assist device (VAD) implantation causes novel arteriovenous malformations. Capillary disturbances and related vascular leakage in the retina and choroidea may also be seen in patients supported by VADs. We aimed to evaluate retinal vasculature deteriorations after VAD implantation. The charts of 17 patients who underwent VAD implantation surgery for the treatment of end-stage heart failure were retrospectively reviewed. Eight cases (47.1%) underwent pulsatile pump implantation (Berlin Heart EXCOR, Berlin Heart Mediprodukt GmbH, Berlin, Germany); however, nine cases (52.9%) had continuous-flow pump using centrifugal design (HeartWare, HeartWare Inc., Miramar, FL, USA). Study participants were selected among the patients who had survived with a VAD for at least 6 months, and results of detailed ophthalmologic examinations including optic coherence tomography (OCT) and fundus fluorescein angiography (FA) were documented. All of the 17 patients were male, with a mean age of 48.5 ± 14.8 years (15-67 years). Detailed ophthalmologic examinations including the evaluation of retinal vascular deteriorations via FA were performed at a mean of 11.8 ± 3.7 months of follow-up (6-18 months). Mean best-corrected visual acuity and intraocular pressure were found as logMAR 0.02 ± 0.08 and 14.6 ± 1.9 mm Hg, respectively in the study population. Dilated fundoscopy revealed severe focal arteriolar narrowing in two patients (11.8%), and arteriovenous crossing changes in four patients (23.5%); however, no pathological alteration was present in macular OCT scans. In patients with continuous-flow blood pumps, mean arm-retina circulation time (ARCT) and arteriovenous transit time (AVTT) were found to be 16.8 ± 3.0 and 12.4 ± 6.2 s, respectively; whereas those with pulsatile-flow blood pumps were found to be 17.4 ± 3.6 and 14.0 ± 2.1 s in patients (P=0.526 and P=0.356, respectively). FA also revealed a tendency for increased frequency of dye leakage from the optic disc in our study population. Except for remarkable delays in both ARCT and AVTT as well as a tendency for increased frequency of dye leakage from the optic disc, ophthalmologic evaluations revealed no other significant pathology or vascular deterioration in the retina that could be attributed to artificial heart systems.

Utility of CHA2DS2-VASc and HAS-BLED Scores as Predictor of Thromboembolism and Bleeding After Left Ventricular Assist Device Implantation

Ischemic and hemorrhagic events are the common causes of morbidity and mortality after continuous-flow left ventricular assist device (CF-LVAD) implantation. CHA2DS2-VASc score predicts thromboembolic (TE) event risk and HAS-BLED score predicts bleeding risk in patients on anticoagulant with atrial fibrillation (AF). We aimed to evaluate whether these scoring systems would be predictive of TE and bleeding complications after CF-LVAD implantation. From December 2010 to December 2014, 145 patients who underwent CF-LVAD implantation at a single center were included. Mean age was 50.7 ± 11.2 years, and 85.5% were male. Baseline CHA2DS2-VASc and HAS-BLED scores were retrospectively determined for patients with CF-LVADs. After device implantation, all patients were on warfarin (target international normalized ratio 2–3) as well as 300 mg of aspirin daily. Median length of support was 316 days (range 31–1,060), with 22 TE events (15.2%) and 32 bleeding (22.1%) events. The mean CHA2DS2-VASc score was 2.3 ± 1.4 and 2.5 ± 1.2 (p = 0.2) in patients with and without TE event, respectively. The mean HAS-BLED score was 1.8 ± 0.8 and 1.42 ± 0.6 (p = 0.004) in patients with and without bleeding, respectively. Baseline high HAS-BLED score was predictive of bleeding events after CF-LVAD implantation, whereas baseline CHA2DS2-VASc score was not predictive of TE events.

Outcomes of Various Treatment Strategies for Patients with Continuous-Flow Ventricular Assist Device Thrombosis: A Retrospective Analysis.

Pump thrombosis is associated with high morbidity and mortality in patients with a continuous-flow left ventricular assist device. Although it has been defined clearly, the diagnosis and treatment of this complication still remain controversial. Between 2010 and 2014, 163 consecutive patients (mean age: 50.7 ± 13 years, 84% males, median duration of support: 277 (2–1077) days) were implanted a continuous-flow left ventricular assist device. Prospectively collected data of all patients who had at least one pump thrombosis event have been analyzed, retrospectively. Twenty-one pump thrombosis events were observed in 15 patients (9.2%, 0.137 events/patient-year). Median duration of support at the time of first pump thrombosis event was 259 (8–585) days. Overall mortality was 40% (6/15), and overall procedural success was 71.4% (15/21) in our entire cohort. The cause of mortality was hemorrhagic stroke in those who had medical treatment (n = 5), and sepsis and right ventricular failure in the other who had pump exchange. Pump exchange was performed in five patients, of which four survived. Glycoprotein IIb/IIIa antagonists are not beneficial in medical treatment of pump thrombosis. Medical treatment methods including unfractionated heparin and thrombolytics may completely resolve the thrombus and save some patients from pump exchange. In patients where medical treatment does not result in complete thrombus resolution within a reasonable period, and a donor heart is not available, pump exchange is the ultimate solution. Further studies are needed for optimal dosing of thrombolytics to decrease the rate of side effects.

Evaluation of Changes in Quality of Life Among Turkish Patients Undergoing Ventricular Assist Device Implantation

BACKGROUND Ventricular assist device (VAD) application has become an increasingly common method to treatment end-stage heart failure. In this study we evaluated the effect of VAD implantation upon the quality of life among Turkish patients with end-stage heart failure. METHODS Twenty-eight VAD implantation patients included 3 (10.7%) with biventricular support using the Berlin Heart Excor; 15 (53.6%), left ventricular support with the Berlin Heart Excor; and 10 (35.7%), Heartware implantation for left ventricular support. The Minnesota Living with Heart Failure Questionnaire (MLHFQ) and Short Form 36 (SF-36) Health Questionnaire were used to assess changes in the quality of life (QOL). RESULTS Of the 28 patients, 2 were females (7.1%) and 26 were males (92.9%) of overall mean age of 44.6 ± 15.3 years (range, 8-66). Preoperative mean score of MLHFQ was significantly improved at 200.4 ± 147.4 days follow-up (72.8 ± 11.5 vs 13.7 ± 10.5; P < .05). SF-36 physical scores and mental scores were improved postoperatively (physical scores, 20.0 ± 24.4 vs 70.2 ± 19.9; mental scores, 38.4 ± 18.8 vs 73.9 ± 15.7; P < .05). No significant relation was observed between the postoperative scores of questionnaires and type of surgery. More improvement in postoperative MLHFQ scores was seen in patients younger than 45 years of age (P = .027). The severity of chronic heart failure (CHF) regressed from New York Heart Association (NYHA) class IV to NYHA class II in 26 and to NYHA class III in 2 patients (P = .000). CONCLUSION The QOL among patients with end-stage heart failure improved dramatically soon after VAD implantation.

Left ventricular assist device implantation with left lateral thoracotomy with anastomosis to the descending aorta

OBJECTIVES Standard implantation of the HeartWare left ventricular assist system is performed using the full sternotomy approach. However, successful implantation of left ventricular assist devices in patients with a previous median sternotomy, especially in high-risk patients, remains challenging. Herein, we compared the HeartWare left ventricular assist system implantation by thoracotomy with anastomosis of the outflow graft to the descending aorta with the standard sternotomy approach. METHODS Between March 2013 and June 2016, we implanted 118 adult patients with a HeartWare left ventricular assist system, excluding implants with concurrent procedures, paediatric cases and biventricular left ventricular assist device. Of these implants, 30 implants were performed with a lateral thoracotomy with outflow graft anastomosis to the descending aorta. The remaining implants were carried out with the standard median sternotomy with outflow graft anastomosis to the ascending aorta. Propensity matching using the variables age, body mass index, right atrial pressure, blood urea nitrogen, creatinine, cardiomyopathy type and Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) levels resulted in a comparative data set of 30 thoracotomy and 30 sternotomy patients. RESULTS Within the first 30 days, the incidence of right heart failure (17% vs 10%, thoracotomy vs sternotomy) and bleeding (10% vs 7%, respectively) were similar between the surgical approaches. Thirty-day survival was 93.3% for both groups. Currently, 3 patients in the thoracotomy cohort have been transplanted and 17 remain on support, while in the sternotomy cohort, 1 patient has been transplanted and 21 remain on support. CONCLUSIONS In our single-centre experience, the lateral thoracotomy with outflow graft anastomosis to the descending aorta had similar early outcomes compared to the standard sternotomy.