Oral amiodarone and propranolol in maintenance therapy of postimplantation tachycardia: An observational study.

Left ventricular assist devices (LVADs) are widely used as end-stage therapy in patients with advanced heart failure, whereas implantation increases the risks of development of sustained ventricular tachycardia at the later postimplantation stage. Therefore, this study aimed to evaluate the clinical efficacy of orally administered amiodarone and propranolol in 3 patients with ventricular tachycardia (VT) after LVAD implantation who were resistant to initial anti-antiarrhythmic drugs. This retrospective cohort study consisted of the initial evaluation of the clinical data of 14 adult patients who underwent implantation of LVAD between January 2019 and March 2021. A total of 3 patients with resistant VT were finally included. In all cases, the patients were initially administered amiodarone in the different doses intravenously to stabilize the critical condition, whereas its oral form along with that of propranolol was used as maintenance therapy in the first 2 cases. In the third case, amiodarone was withdrawn because of the risk of development of hyperthyroidism, while oral propranolol was used in the treatment. The assessment in the 16-month follow-up period after discharge did not show presence of non-sustained and sustained VT in all 3 cases. In the ventricular arrhythmia-free group, the total mortality rate within the follow-up period was 11.1 ±â€…7.78 months in the 3 patients. We suggest that maintenance oral therapy of propranolol and amiodarone can significantly decrease the risks of complications in patients with VT after implantation of ventricular assist device in the long term.

Acausal Modelling of Advanced-Stage Heart Failure and the Istanbul Heart Ventricular Assist Device Support with Patient Data.

BACKGROUND: In object-oriented or acausal modelling, components of the model can be connected topologically, following the inherent structure of the physical system, and system equations can be formulated automatically. This technique allows individuals without a mathematics background to develop knowledge-based models and facilitates collaboration in multidisciplinary fields like biomedical engineering. This study conducts a preclinical evaluation of a ventricular assist device (VAD) in assisting advanced-stage heart failure patients in an acausal modelling environment. METHODS: A comprehensive object-oriented model of the cardiovascular system with a VAD is developed in MATLAB/SIMSCAPE, and its hemodynamic behaviour is studied. An analytically derived pump model is calibrated for the experimental prototype of the Istanbul Heart VAD. Hemodynamics are produced under healthy, diseased, and assisted conditions. The study features a comprehensive collection of advanced-stage heart failure patients' data from the literature to identify parameters for disease modelling and to validate the resulting hemodynamics. RESULTS: Regurgitation, suction, and optimal speeds are identified, and trends in different hemodynamic parameters are observed for the simulated pathophysiological conditions. Using pertinent parameters in disease modelling allows for more accurate results compared to the traditional approach of arbitrary reduction in left ventricular contractility to model dilated cardiomyopathy. CONCLUSION: The current research provides a comprehensive and validated framework for the preclinical evaluation of cardiac assist devices. Due to its object-oriented nature, the featured model is readily modifiable for other cardiovascular diseases for studying the effect of pump operating conditions on hemodynamics and vice versa in silico and hybrid mock circulatory loops. The work also provides a potential teaching tool for understanding the pathophysiology of heart failure, diagnosis rationale, and degree of assist requirements.

In-silico hemodynamic ramp testing of ventricular assist device implanted patients using acausal cardiovascular-VAD modeling.

BACKGROUND: While cardiovascular system and mechanical circulatory support devices are efficiently model the effect of disease and assistance, they can also lend valuable insights into clinical procedures. This study demonstrates the use of a CVS-VAD model for an invasive procedure; hemodynamic ramp testing, in-silico. METHODS: The CVS model is developed using validated models in literature, using Simscape™. An analytically derived pump model is calibrated for the HeartWare VAD. Dilated cardiomyopathy is used as an illustrative example of heart failure, and heart failure patients are created virtually by calibrating the model with requisite disease parameters obtained from published patient data. A clinically applied ramp study protocol is adopted whereby speed optimization is performed following clinically accepted hemodynamic normalization criteria. Trends in hemodynamic variables in response to pump speed increments are obtained. Optimal speed ranges are obtained for the three virtual patients based on target values of central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), cardiac output (CO), and mean arterial pressure (MAP) for hemodynamic stabilization. RESULTS: Appreciable speed changes in the mild case (300 rpm), slight changes in the moderate case (100 rpm), and no changes in the simulated severe case are possible. CONCLUSION: The study demonstrates a novel application of cardiovascular modeling using an open-source acausal model, which can be potentially beneficial for medical education and research.

A Short-Term In Vivo Evaluation of the Istanbul Heart Left Ventricular Assist Device in a Pig Model.

OBJECTIVES: A continuous-flow centrifugal blood pump system has been recently developed as an implantable left ventricular assist device for patients with endstage heart failure. The objective of this study was to evaluate the initial in vivo performance of a newly developed left ventricular assist device (iHeart or Istanbul heart; Manufacturing and Automation Research Center, Koc University, Istanbul, Turkey) in an acute setting using a pig model. MATERIALS AND METHODS: Three pigs (77, 83, 92 kg) received implants via a median sternotomy, with animals supported for up to 6 hours. An outflow cannula was anastomosed to the ascending aorta. Anticoagulation was applied by intravenous heparin administration. During the support period, pump performance was evaluated under several flow and operating conditions. All pigs were humanely sacrificied after the experiments, and organs were examined macroscopically and histopathologically. RESULTS: Flow rate ranged between 1.5 and 3.6 L/min with pump speeds of 1500 to 2800 revolutions/min and motor current of 0.6 to 1.3 A. Initial findings confirmed thatthe iHeart ventricular assist device had sufficient hydraulic performance to support the circulation. During the experimental period, plasma free hemoglobin levels were found to be within normalranges.Thrombus formation was not observed inside the pump in all experiments. CONCLUSIONS: The iHeart ventricular assist device demonstrated encouraging hemodynamic performance and good biocompatibility in the pig model for use as an implantable left ventricular assist device. Further acute in vivo studies will evaluate the short-term pump performance prior to chronic studies for long-term evaluation.

Fine-tuning management of the Heart Assist 5 left ventricular assist device with two- and three-dimensional echocardiography.

INTRODUCTION: Left ventricular assist device (LVAD) implantation is a viable therapy for patients with severe end-stage heart failure, providing effective haemodynamic support and improved quality of life. The Heart Assist 5 (Micromed Cardiovascular Inc, Houston, TX) continuous-flow LVAD has been on the market in Europe since May 2009. METHODS: We evaluated nine Heart Assist 5 LVAD patients with two- and three-dimensional transthoracic echocardiographic (TTE) and transoesophageal echocardiographic (TEE) parameters between December 2011 and December 2013. The pre-operative TTE LVAD evaluations included left ventricular (LV) function and structure, quantification of right ventricular (RV) function and tricuspid regurgitation (TR), assessment of aortic and mitral regurgitation, and presence of patent foramen ovale and intra-cardiac clots. Peri-operative TEE determined the inflow cannula and septum position, and assessed the de-airing process while weaning from cardiopulmonary bypass. Post-operative serial follow-up TTE showed the surgical results of LVAD implantation, determined the overall structure and function of the LV, RV and TR, and observed the inflow and outflow cannula position. RESULTS: Nine patients who had undergone Heart Assist 5 LVAD implantation and had been followed up for more than 30 days were included in this study. Eight patients had ischaemic cardiomyopathy and one had adriamycin-induced cardiomyopathy. Pre-implantation data: the mean age of the patients was 52 ± 13 (34-64) years, mean body surface area (BSA) was 1.8 ± 0.2 (1.6-2.0) m2, mean cardiac index (CI) was 2.04 ± 0.4 (1.5-2.6) l/min/m2, mean cardiac output (CO) was 3.7 ± 0.7 (2.6-4.2) l/min, mean ejection fraction (EF) was 23 ± 5 (18-28)%, and right ventricular fractional area contraction (RVFAC) was 43 ± 9 (35-55)%. One patient had aortic valve replacement (AVR) during the LVAD implantation, and excess current alarms and increased power were suspected to be caused by a possible thrombus. Close follow up with TTE studies were carried out to clear the LV of thrombus formation, and the inflow cannula position was checked to maintain the septum in the midline, so preventing the suction cascade. Four patients were followed up for more than two years, and two were followed up for more than a year. Three patients died due to multi-organ failure. Follow-up speed-change TTE studies of six patients showed that the mean speed was 9 800 ± 600 (9 500-10 400) rpm, and mean CO was 4.7 ± 0.3 (4.3-5.0) l/min during the three-month post-implant period. CONCLUSION: We believe that TTE can play a major role in managing LVAD patients to achieve optimal settings for each patient. A large series is mandatory for assessment of echocardiographic studies on Heart Assist 5 LVAD.

Remote monitoring of left ventricular assist device parameters after HeartAssist-5 implantation.

Although several left ventricular assist devices (LVADs) have been used widely, remote monitoring of LVAD parameters has been available only recently. We present our remote monitoring experience with an axial-flow LVAD (HeartAssist-5, MicroMed Cardiovascular, Inc., Houston, TX, USA). Five consecutive patients who were implanted a HeartAssist-5 LVAD because of end-stage heart failure due to ischemic (n=4) or idiopathic (n=1) cardiomyopathy, and discharged from hospital between December 2011 and January 2013 were analyzed. The data (pump speed, pump flow, power consumption) obtained from clinical visits and remote monitoring were studied. During a median follow-up of 253 (range: 80-394) days, fine tuning of LVADs was performed at clinical visits. All patients are doing well and are in New York Heart Association Class-I/II. A total of 39 alarms were received from three patients. One patient was hospitalized for suspected thrombosis and was subjected to physical examinations as well as laboratory and echocardiographic evaluations; however, no evidence of thrombus washout or pump thrombus was found. The patient was treated conservatively. Remaining alarms were due to insufficient water intake and were resolved by increased water consumption at night and summer times, and fine tuning of pump speed. No alarms were received from the remaining two patients. We believe that remote monitoring is a useful technology for early detection and treatment of serious problems occurring out of hospital thereby improving patient care. Future developments may ease troubleshooting, provide more data from the patient and the pump, and eventually increase physician and patient satisfaction. Despite all potential clinical benefits, remote monitoring should be taken as a supplement to rather than a substitute for routine clinical visits for patient follow-up.

Endovenous laser ablation with 980-nm diode laser: early and midterm results.

OBJECTIVE: Endovenous laser ablation (EVLA) is an efficient method to treat incompetent great saphenous veins (GSV) with high occlusion rates. The aim of this prospective study is to demonstrate the treatment outcomes of EVLA of incompetent GSV with a 980-nm diode laser in an ambulatory setting. BACKGROUND DATA: EVLA of the incompetent GSV with a 980-nm diode laser appears to be an extremely safe technique. There are several treatment alternatives available. Among the emerging techniques, EVLA is one of the most promising. METHODS: Ninety eight patients (103 limbs) with symptomatic varicose veins secondary to GSV insufficiency treated with 980-nm EVLA were prospectively studied. In all patients, laser energy was administered with constant pullback of fiberoptic laser catheter under tumescent anesthesia. The patients were assessed and followed by clinical examination and venous duplex ultrasonography. Pain scores of the patients from discharge to their first follow-up visit (7 days) were recorded by using visual analog scale (VAS). Patient satisfaction was assessed and recorded at 6 month follow-up. RESULTS: All patients tolerated EVLA procedure well, and were discharged from hospital on the same day with ablation procedure. The overall success rate was 97.5% in 98 patients. Mean length of measured treated vein segment was 29.93±6.36 cm. Mean applied total energy was 2006.24±480.16 J. Major complications such as deep vein thrombosis and skin burns were not seen. Most of the complications were minor and improved quickly. All patients returned to daily activities within 2 days. CONCLUSIONS: EVLA of the GSV insufficiency using 980-nm diode laser is an effective and safe technique with a high patient satisfaction rate. The advantages of the procedure are that it is performed as an outpatient procedure, provides early mobilization, causes minimal cessation of daily activities, and avoids classic surgical complications.

A new practical alternative for the control of sternal bleeding during cardiac surgery: Ankaferd Blood Stopper.

The control of sternal bleeding during cardiac surgery can sometimes be a challenging and time-consuming problem for surgeons. Several alternatives for the control of sternal bleeding are on the market. Bone wax is a well-known alternative used by many cardiac surgeons for the control of bleeding. It is effective and cheap; however, it inhibits ossification of the sternum and can cause infections and sternal wound healing problems after cardiac surgery. Consequently, control of sternal bleeding without the use of bone wax requires meticulous preparation. Ankaferd Blood Stopper (ABS) (Ankaferd Saglik Ürünleri, Istanbul, Turkey) is a unique folkloric medicinal plant extract that has been used in Turkish traditional medicine as a hemostatic agent. We present a practical alternative technique for the control of sternal bleeding during cardiac surgery with the use of ABS.

Sarcoidosis and coronary bypass surgery: a case report.

Sarcoidosis, a chronic granulomatous disease with unknown etiology and pathogenesis, affects the skin and many other organs and has a course characterized by remissions and relapses. We describe a patient with sarcoidosis, which we diagnosed retrospectively after we had difficulties in harvesting the left internal thoracic artery because of giant and disseminated mediastinal lymphadenopathies on the anterior thoracic wall during urgent coronary artery bypass surgery.

Comparison of pulsatile and non-pulsatile cardiopulmonary bypass in patients with chronic obstructive pulmonary disease.

BACKGROUND: Patients with chronic obstructive pulmonary disease have an increased risk of mortality and morbidity after open-heart surgery. This is mostly due to a dysfunction of the pulmonary system during and after non-pulsatile cardiopulmonary bypass. The purpose of this study was to compare the pulsatile and non-pulsatile blood flows during cardiopulmonary bypass in patients with chronic obstructive pulmonary disease. MATERIAL/METHODS: This is a prospective study. Ten patients with chronic obstructive pulmonary disease had open-heart surgery with pulsatile flow, and another 9 patients with non-pulsatile flow. We compared clinical, hemodynamic, biochemical and hematological parameters and arterial and venous blood gases before initiating cardiopulmonary bypass, at aortic cross-clamping and de-clamping, and 1 and 24 hours postoperative. RESULTS: In the pulsatile flow group, systemic vascular resistance at the time of aortic cross clamping (p=0.041), pulmonary vascular resistance 1 hour postoperative (p=0.05), and the percentage of neutrophils 1 hour postoperative (p=0.034) were significantly lower than those of the non-pulsatile group. Though white blood cell count was significantly high in the pulsatile group 1 hour postoperative, absolute neutrophil count was significantly low (p=0.034). The postoperative mechanical ventilation period was significantly shorter in the pulsatile flow group (p=0.016). CONCLUSIONS: Pulsatile blood flow during cardiopulmonary bypass has a favorable influence on patients with chronic obstructive pulmonary disease, who have high risk in open-heart surgery.

Dynamic cardiomyoplasty as a biomechanic bridge to heart transplantation.

We report a heart transplantation that was done 4 years after a dynamic cardiomyoplasty operation. The patient was a 42-year-old man. Radionucleide ventriculography with technetium 99 m revealed an ejection fraction of 18%. In July 1997 he had undergone a dynamic cardiomyoplasty operation. At the first postoperative month the left ventricular ejection fraction was 35%. In September 2000 he presented with heart failure symptoms. In May 2001 he had undergone heart transplantation. Postoperative course was uneventful. The failure of cardiomyoplasty was probably caused by degeneration of the latissimus dorsi muscle. In this case we have learned that muscle viability is lost within 4 years after dynamic cardiomyoplasty and heart transplantation is still an option for those patients.

First Turkish experience with the MicroMed DeBakey VAD.

Mechanical bridging to cardiac transplantation with a ventricular assist device may be a life-saving procedure for patients with end-stage heart failure. Here we report our 3 cases of patients implanted with the MicroMed DeBakey VAD (ventricular assist device). Three male patients, aged 37, 41, and 40, had end-stage left heart failure due to idiopathic cardiomyopathy and were listed for cardiac transplantation. They had progressive hemodynamic deterioration. Although Patient 1 underwent surgery, after device implantation, for bowel necrosis caused by thromboemboli of unknown origin, heart transplantation was performed 70 days after implantation. Pump thrombosis occurred in Patient 2 on the 120th day. Outflow graft ligation was performed because the patient refused a pump exchange. This patient died on the 25th day after ligation and the 145th day after ventricular assist device implantation. A heparin-coated version of the device was implanted in Patient 3, whose preoperative profound biventricular failure had been improved by inotropic medication and intra-aortic balloon pump support. Successful heart transplantation was performed 161 days after implantation. These are the 1st implantations of a left ventricular assist device in Turkey. From these cases, we have learned that the DeBakey VAD supplies adequate blood flow during the bridging period and, due to its simplicity, portability, and low infection rate, enables discharge of the patient from the hospital. However, preoperative psychological evaluation and postoperative psychological support are important for a successful bridging procedure, as is close observation of coagulation and of pump operation.

Do S100beta protein level increases due to inflammation during cardiopulmonary bypass occur without any neurological deficit?

PURPOSE: S100beta protein level correlates with the duration of cardiopulmonary bypass (CPB) and aortic crossclamp times, but is different during pulsatile and nonpulsatile CPB. In this study, we investigated the time course of the release of S100beta protein during and after pulsatile and nonpulsatile CPB. PATIENTS AND METHODS: This is a prospective study. Twenty patients had open-heart surgery with pulsatile flow and 20 with nonpulsatile flow. We compared complement proteins, interleukins, white blood cells and S100beta protein before the initiation of CPB, immediately prior to aortic crossclamping, following unclamping, and at postoperative 1st and 24th hours. RESULTS: In the pulsatile CPB group following aortic unclamping, S100beta protein (p = 0.028) and C3a (p = 0.011) levels were significantly lower than those of the nonpulsatile group. In the pulsatile CPB group at postoperative first hour, C3a level (p = 0.018) and absolute neutrophil count (p = 0.034) were significantly lower than those of the nonpulsatile group. None of the patients developed a neurological deficit and all of the patients survived after the operation and were discharged from the hospital. CONCLUSION: During CPB, serum S100beta protein level increases and this increase is higher in the nonpulsatile group. High serum level of S100beta protein is associated with increased levels of serum inflammatory mediators and systemic inflammatory response.