AIMS: The HeartMate 3 (HM3) implantable left ventricular assist device connects the left ventricle apex to the aorta via an outflow graft. Extrinsic obstruction of the graft (eOGO) is associated with serious morbidity and mortality and recently led to a Food and Drug Administration Class 1 device recall of HM3. This study aimed to provide a better understanding of the haemodynamic impact of extrinsic stenoses.

METHODS AND RESULTS: Computed tomography (CT) images of two retrospectively identified patients with eOGO (29 and 36% decrease in cross-sectional area, respectively, by radiological evaluation) were acquired with a novel photon-counting CT system. Numerical evaluations of haemodynamics were conducted using a high-fidelity 3D computational fluid dynamics approach on both the patient-specific graft geometries and in two virtually augmented stenotic severities and three device flows. Visual analysis identified increased velocity, pressure, and turbulent flow in the outer anterior curvature of the outflow graft; however, changes in graft pressure gradients were slight (1-9 mmHg) across the range of stenosis severities and flow rates tested.

CONCLUSION: Evidence of eOGO during HM3 support and the recent device recall can provoke clinical apprehension and interventions. The haemodynamic impact of a stenosis detected visually or by quantification of cross-sectional area reduction may be difficult to predict and easily overestimated. This numerical study suggests that, for clinically encountered flow rates and stenosis severities below 61% in cross-sectional area decrease, eOGO may have low haemodynamic impact. This suggests that patients without symptoms or signs consistent with haemodynamically significant obstruction might be managed expectantly.

Background: The prevalence of aortic valve stenosis (AS) is increasing due to an ageing population. Despite that right ventricular function has prognostic value for postoperative outcome, the right ventricle (RV) is not extensively studied and often not routinely assessed in AS. Our aim was to explore the relation between severe AS and RV function in a surgical aortic valve replacement (SAVR) cohort, comparing two imaging modalities for RV evaluation.Methods: Patients with severe AS, underwent cardiovascular magnetic resonance imaging (CMR) and transthoracic echocardiography (TTE) before SAVR. RV dysfunction was defined as one or more of the following: tricuspid annular plane systolic excursion (TAPSE) < 17 mm, RV free wall strain (RVFWS) > -20% by TTE and RV ejection fraction (RVEF) <50% by CMR.Results: Sixteen (33%) patients were found to have RV dysfunction. Patients with RV dysfunction showed significantly lower indexed aortic valve area, left ventricular (LV) ejection fraction as well as RV and LV stroke volumes compared to patients with maintained RV function. All patients with reduced RVEF also had changes in TAPSE or RVFWS and a larger number of patients had a reduced longitudinal RV function despite a normal RVEF.Conclusion: In a SAVR cohort one-third of the patients had RV dysfunction, defined by RVEF, TAPSE or RVFW strain. Echocardiography detected subtle changes in RV function before RVEF was reduced. It is likely that the more pronounced the AS, the more frequent the occurrence of RV dysfunction.

BACKGROUND: The pectoralis major flap, which is usually harvested bilaterally, is considered a workhorse flap in the reconstruction of sternal defects. After a median sternotomy for open heart surgery, 1%-3% of patients develop deep infection and dehiscence of the sternal wound, some of which will eventually require reconstructive surgery. Our aim was to describe the clinical feasibility and associated complications of the unilateral pectoralis major advancement flap in the reconstruction of sternal defects.

METHODS: A retrospective analysis of all adult patients who were operated on using a unilateral pectoralis major flap for reconstruction of the chest wall at the Linköping University Hospital during 2008-18 was made using data retrieved from medical records.

RESULTS: Forty-three patients had reconstructions with unilateral pectoralis major flaps. Three flaps failed completely, and another 10 patients developed complications that required further operation. The factors that were independently associated with loss of the flaps and complications were: older age, male sex, the number of different antibiotics used, and a long duration of treatment with negative wound pressure. Fewer wound revisions before the reconstruction resulted in more complications. The factors that were independently associated with prolonged time to complete healing were emergency reoperation after the initial operation and complications after reconstruction.

CONCLUSION: The unilateral pectoralis major advancement flap has proved to be a useful technique in the reconstruction of most sternal defects after sternal wound infection in older patients. There is, however, need for a follow-up study on a larger number of procedures to evaluate the long-term outcome compared with other methods of sternal reconstruction.

INTRODUCTION: The HeartMate 3^™ has shown lower rates of adverse events compared to previous devices due to the design and absence of mechanical bearings. For previous devices, sound analysis emerged as a way to assess pump function. The aims of this study were to determine if sound analysis can be applied to the HeartMate 3 in vivo and in vitro and to evaluate an electronic stethoscope.

METHOD: Sound recordings were performed with microphones and clinical accessible electronic stethoscope. The recordings were studied in both the time and the frequency domains. Recordings from four patients were performed to determine if in vivo and in vitro recordings are comparable.

RESULTS: The results show that it is possible to detect sound from HeartMate 3 and the sound spectrum is clear. Pump frequency and frequency of the pulsatile mode are easily determined. Frequency spectra from in vitro and in vivo recordings have the same pattern, and the major proportion (96.7%) of signal power is located at the pump speed frequency ±40 Hz. The recordings from the patients show low inter-individual differences except from location of peaks originating from pump speed and harmonics. Electronic stethoscopes could be used for sound recordings, but the dedicated equipment showed a clearer sound spectrum.

DISCUSSION: The results show that acoustic analysis can also be performed with the HeartMate 3 and that in vivo and in vitro sound spectrum is similar. The frequency spectra are different from previous devices, and methods for assessing pump function or thrombosis need further evaluation.

Introduction: The use of left ventricular assist device (LVAD) has grown rapidly. Adverse events do continue to occur. In recent years, analysis of LVAD sound recordings emerged as a means to monitor pump function and detect pump thrombosis. The aim of this study was to characterize the sounds from HeartMate II and to evaluate the use of handheld iOS devices for sound recordings. Method: Signal analysis of LVAD sound recordings, with dedicated recording equipment and iOS devices, was performed. Two LVADs running in mock loop circuits were compared to an implanted LVAD. Spectral analysis and parametric signal models were explored to quantify the sound and potentially detect changes in it. Results: The sound recordings of two LVADs in individual mock loop circuits and a third one implanted in a patient appeared to be similar. Qualitatively, sound characteristics were preserved following changes in pump speed. Recordings using dedicated equipment showed that HeartMate II sound comprises low-frequency components corresponding to pump impeller rotation, as well as high-frequency components due to a pulse width modulation of the electric power to the pump. These different signal components interact and result in a complicated frequency spectrum. The iPhone and iPod recordings could not reproduce the sounds as well as the dedicated equipment. In particular, lower frequencies were affected by outside disturbances. Discussion: This article outlines a systematic approach to LVAD sound analysis using signal processing methods to quantify and potentially detect changes, and describes some of the challenges, for example, with the use of inexpensive recording devices.

OBJECTIVES: Our goal was to validate the Swedish Cardiac Surgery Registry by reviewing the reported cardiac operations to assess the completeness and quality of the registered data and the EuroSCORE II variables. METHODS: A total of 5837 cardiac operations were reported to the Swedish Cardiac Surgery Registry in Sweden during 2015. A randomly selected sample of 753 patient records (13%) was scrutinized by 3 surgeons at all 8 units in Sweden performing open cardiac surgery in adults. RESULTS: Coverage was excellent with 99% [95% confidence interval (CI) 98-99%] of the performed procedures found in the registry. Reported waiting times for surgery were correct in 78% (95% CI 76-79%) of the cases. The main procedural code was correctly reported in 96% (95% CI 95-97%) of the cases. The correlation between reported and monitored logistic EuroSCORE II had a coefficient of 0.79 (95% CI 0.76-0.82), and the median difference in EuroSCORE II was 0% (interquartile range -0.4% to 0.4%). The majority of EuroSCORE II variables had good agreement and coherence; however, New York Heart Association functional class, preoperative renal dysfunction, left ventricular ejection fraction, Canadian Cardiovascular Society Class IV angina and poor mobility were less robust Postoperative complications were rare and in general had a high degree of completeness and agreement. CONCLUSIONS: The reliability of the variables in the national Swedish Cardiac Surgery Registry was excellent. Thus, the registry is a valuable source of data for quality studies and research. Some EuroSCORE II variables require improved and stricter definitions to obtain uniform reporting and high validity.

Purpose

The continuous flow mechanical circulatory support HeartMate II^™ (Thoratec Corporation, Inc. Pleasanton, USA) (HMII), generates an auditory signal (acoustic fingerprint) that can be registered by routine auscultation. A temporary or permanent change in sound indicates a change in pump function. Previous mock loop studies have shown that changes in acoustic fingerprint are due to changes in speed, so the aim of this study was to see if the acoustic fingerprint changed during an echocardiographic ramp test.

Methods

Four stable, event-free patients included in the SoundMate study performed an echocardiographic ramp test. The speed was increased stepwise by 400 rpm between 8 000 and 12 000 rpm, and the left ventricular end diastolic diameter, flow, power consumption and blood pressure were measured. Sounds from HMII were recorded using an iPhone™ (Apple Inc. Cupertino, CA, USA) with the stethoscope application iStethPro™ (Dr. Peter J Bentley, UK) and the frequency map analyzed using the Audacity™ program (Unicode, Ash, Chinen and Crook, USA). The acoustic fingerprint is divided into regions (R1: 1 000-6 500, R2: 8 500-14 000, R3: 15 000-21 000 Hz) and peaks (P1: 0-1 000, P2: 6 500-8 500, P4: 21 000-23 000 Hz) in order to facilitate calculations and clarify changes in frequency.

Results

There were significant (p<005) changes in the acoustic fingerprint when increasing the pump speed between 8 000 and 12 000 rpm. In 2/4 patients there were no significant changes in P1, otherwise there were significant changes in all regions and peaks. During the ramp test the power increased in mean 7 W, flow 3,1 L/min and the blood pressure measured with Doppler increased by ~15 mmHg. The left ventricular size decreased with ~2 cm.

Conclusion

The acoustic fingerprint changes with pump speed. This implies that when using sound check for detection of pump dysfunction, a new baseline should be set after every adjustment of speed.

Mechanical circulatory support technology is continually improving. However, adverse complications do occur with devastating consequences, for example, pump thrombosis that may develop in several parts of the pump system. The aim of this study was to design an experimental clot/thrombosis model to register and analyze acoustic signals from the left ventricular assist device (LVAD) HeartMate II (HMII) (Thoratec Corporation, Inc., Pleasanton, CA, USA) and detect changes in sound signals correlating to clots in the inflow, outflow, and pump housing. Using modern telecom techniques, it was possible to register and analyze the HMII pump-specific acoustic fingerprint in an experimental model of LVAD support using a mock loop. Increase in pump speed significantly (P less than 0.005) changed the acoustic fingerprint at certain frequency (0-23 000 Hz) intervals (regions: R1-3 and peaks: P1,3-4). When the ball valves connected to the tubing were narrowed sequentially by similar to 50% of the inner diameter (to mimic clot in the out-and inflow tubing), the frequency spectrum changed significantly (P less than 0.005) in P1 and P2 and R1 when the outflow tubing was narrowed. This change was not seen to the same extent when the lumen of the ball valve connected to the inflow tube was narrowed by similar to 50%. More significant (P less than 0.005) acoustic changes were detected in P1 and P2 and R1 and R3, with the largest dB figs. in the lower frequency ranges in R1 and P2, when artificial clots and blood clots passed through the pump system. At higher frequencies, a significant change in dB figs. in R3 and P4 was detected when clots passed through the pump system. Acoustic monitoring of pump sounds may become a valuable tool in LVAD surveillance.

Cardiotoxicity is a multifactorial problem, which has emerged with the improvement of cancer therapies and survival. Heart transplantation is relatively contraindicated in patients with breast cancer, until at least 5 years after complete remission. We present a case where a young woman who in 2001, at the age of 31, was diagnosed with breast cancer. She was considered cured, but 4 years later she suffered a relapse. During her second treatment, in 2006, she suffered from severe heart failure. She received a HeartMate II, as a long-term bridge to transplantation and 6 years later she was successfully transplanted. In this case report we discuss the use of mechanical circulatory support in cancer patients with drug-induced heart failure.