Acetazolamide As A Valuable Addition to Acute Heart Failure?

Consider IV Acetazolamide in addition to standard IV loop diuretic therapy in patients hospitalized for acute decompensated heart failure.1.

The relationship of myocardial and liver T2* values with cardiac function and laboratory findings in transfusion-dependent thalassemia major patients: A retrospective cardiac MRI study

Introduction

Cardiac complications are the leading cause of death in thalassemia patients. It is assumed that progressive iron accumulation results in myocyte damage. Myocardial T2* measurement by cardiac MRI quantifies iron overload. We aimed to study the association between left and right ventricular (LV and RV) function and iron deposition estimation by cardiac MRI T2* in a sample of Iranian patients.

Methods

Cardiac MRI exams of 118 transfusion-dependent thalassemia major patients were evaluated retrospectively. Biventricular function and volume and myocardial and liver T2* values were measured. The demographic and lab data were registered. Poisson and chi-square regression analyses investigated the correlation between the T2* value and ventricular dysfunction.

Results

The study participants' mean (SD) age was 32.7y (9.02), and 47.46% were female. Forty-nine cases (41.52%) revealed at least uni-ventricular dysfunction. LV dysfunction was noted in 20 cases, whereas 47 patients revealed RV dysfunction. The risk of LV dysfunction was 5.3-fold higher in patients with cardiac T2* value less than 10msec (RR=5.3, 95% CI=1.6, 17.1, P<0.05). No association was found between age, liver T2* value, serum ferritin level, and chelation therapy with the risk of LV and RV dysfunction.

Conclusion

Cardiac MRI T2* measure is a good indicator of LV dysfunction. Moreover, MRI parameters, especially RV functional measures, may have a substantial role in patient management. Therefore, cardiac MRI should be included in beta-thalassemia patients' management strategies.

Cardiomyopathy Induced by Artificial Cardiac Pacing: To Whom, When, Why, and How? Insights on Heart Failure Development

Coordinated and harmonic (synchronous) ventricular electrical activation is essential for better left ventricular systolic function. Intraventricular conduction abnormalities, such as left bundle branch block due to artificial cardiac pacing, lead to electromechanical "dyssynchronopathy" with deleterious structural and clinical consequences. The aim of this review was to describe and improve the understanding of all the processes connecting the several mechanisms involved in the development of artificially induced ventricular dyssynchrony by cardiac pacing, most known as pacing-induced cardiomyopathy (PiCM). The chronic effect of abnormal impulse conduction and nonphysiological ectopic activation by artificial cardiac pacing is suspected to affect metabolism and myocardial perfusion, triggering regional differences in the activation/contraction processes that cause electrical and structural remodeling due to damage, inflammation, and fibrosis of the cardiac tissue. The effect of artificial cardiac pacing on ventricular function and structure can be multifactorial, and biological factors underlying PiCM could affect the time and probability of developing the condition. PiCM has not been included in the traditional classification of cardiomyopathies, which can hinder detection. This article reviews the available evidence for pacing-induced cardiovascular disease, the current understanding of its pathophysiology, and reinforces the adverse effects of right ventricular pacing, especially right ventricular pacing burden (commonly measured in percentage) and its repercussion on ventricular contraction (reflected by the impact on left ventricular systolic function). These effects might be the main defining criteria and determining mechanisms of the pathophysiology and the clinical repercussion seen on patients.

Video-Based Deep Learning for Automated Assessment of Left Ventricular Ejection Fraction in Pediatric Patients

BACKGROUND

Significant interobserver and interstudy variability occurs for left ventricular functional indices despite standardization of measurement techniques. Artificial intelligence models trained on adult echocardiograms are not likely to be applicable to a pediatric population. We present EchoNet-Peds, a video-based deep learning algorithm, which matches human expert performance of left ventricular (LV) segmentation and ejection fraction (EF).

METHODS

A large pediatric dataset of 4,467 echocardiograms were used to develop EchoNet-Peds. EchoNet-Peds was trained on 80% of the data for segmentation of the left ventricle and estimation of left ventricular EF. The remaining 20% was used to fine tune and validate the algorithm.

RESULTS

In both apical 4-chamber (A4C) and parasternal short-axis views (PSAX), EchoNet-Peds segments the left ventricle with a Dice similarity coefficient of 0.89. EchoNet-Peds estimates EF with a mean absolute error of 3.66% and can routinely identify pediatric patients with systolic dysfunction (area under the curve of 0.95). EchoNet-Peds was trained on pediatric echocardiograms and performed significantly better to estimate EF (p < 0.001) than an adult model applied to the same data.

CONCLUSION

Accurate, rapid automation of EF assessment and recognition of systolic dysfunction in a pediatric population are feasible using EchoNet-Peds with the potential for far-reaching clinical impact. In addition, the first large pediatric dataset of annotated echocardiograms is now publicly available for efforts to develop pediatric-specific artificial intelligence algorithms.

Protocol-based Surgical Intervention to Manage Ventricular Septal Rupture from a Tier Two City

INTRODUCTION

This study analyzes the outcome of a protocol-based surgical approach for ventricular septal rupture (VSR). The study also clarifies the appropriate time for intervention.

METHODS

This is a single-center retrospective analysis of all VSR cases evaluated between February 2006 and March 2020. Cases were managed using the same protocol. Patients were divided into two cohorts - early (those in whom our protocol was instituted within 24 hours of diagnosis) and delayed (intervention between 24 hours and seven days after diagnosis). All-cause mortality was considered as the outcome.

RESULTS

The mean age of presentation was 60.1 years, and 75.9% of the patients were men. Cardiogenic shock was the most common mode of presentation. Our analysis validates that once a patient develops VSR, age, sex, comorbidities, left ventricular function, and renal failure at the time of presentation do not have a statistically significant impact on the outcome. The sole factor to have an impact on the outcome was time of intervention. All patients in the delayed cohort expired after surgery, which dragged the overall mortality to 34.5%, whereas 95% of patients in the early cohort are still on follow-up. The mortality in this group was 5% (P≤0.001).

CONCLUSION

Early surgical intervention has proven benefits over delayed approach. Surgical intervention in the early part of the disease reduces the risk and thus improves the outcome. The extreme rarity makes VSR an uncommon entity among surgeons. A protocol-based approach makes the team adapt to this unfamiliar situation better.

Laser Lead Extraction During Venoarterial ECMO support

The treatment of valvular endocarditis in patients with cardiac implantable electrophysiological device (CIED) includes valvular surgery and lead extraction. This can be challenging in patients with severely reduced left ventricular ejection fraction (LVEF). Reduced LVEF in combination with sepsis and cardioplegic cardiac arrest can make weaning from cardiopulmonary bypass difficult. Some of these patients require venoarterial extracorporeal membrane oxygenation (VA-ECMO) for postcardiotomy syndrome. Lead extraction by manual traction is often not possible in cases with a long lead dwell time. Therefore, a lead extraction procedure with powered sheaths is required during the VA-ECMO support. We describe our technique for laser lead extraction during VA-ECMO support in a 64-year-old patient with triple valve endocarditis and lead vegetations.

Effects of BPA on right ventricular mechanical dysfunction in patients with inoperable CTEPH - A cardiac magnetic resonance study

PURPOSE

The aim of this study was to assess effects of balloon pulmonary angioplasty (BPA) on right ventricular (RV) mechanical dysfunction in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) via MRI.

METHOD

MRI at 1.5 Tesla and right heart catheterization were performed before and 6 months after BPA in 30 CTEPH patients (mean age 63.4 ± 10.6 years; 17 female). Feature-tracking strain analysis, including global longitudinal (GLS), circumferential (GCS), and radial (GRS) strain, was performed and compared with right ventricular function, myocardial remodelling (assessed by native T1 times), and pulmonary haemodynamics (mean pulmonary arterial pressure and pulmonary vascular resistance).

RESULTS

RVEF (35.9% to 48.4%) increased and mPAP (42.1 mmHg to 33.1 mmHg) and PVR (551.8 to 377.7 dyn∙s/cm⁵) decreased after BPA (all p < 0.0001). Moreover, RV strain increased (GLS -19.9 to -24.0%, p = 0.0003; GCS -9.4 to -11.0%, p = 0.0022; GRS 38.2 to 50.7%, p = 0.001) and septal native area-adjusted T1 time (AA-T1) decreased (1019.4 to 988.7 ms, p < 0.0001). GLS revealed the best correlations with RVEF (before BPA r = -0.75; after BPA r = -0.54), mPAP (r = 0.36; r = 0.52), PVR (r = 0.49; r = 0.48), and AA-T1 (r = 0.44; 0.19).

CONCLUSION

RV mechanical dysfunction, pulmonary haemodynamics, and myocardial remodelling are markedly improved by BPA. Moreover, RV strain values showed good correlations with RV function, pulmonary haemodynamics, and myocardial remodelling. Therefore, strain analysis might provide new insights regarding therapy outcome, monitoring, and prognosis.

Influence of Bentall Procedure on Left Ventricular Function

Objective

To evaluate the influence of Bentall procedure on left ventricular function and condition on long-term follow-up.

Methods

Seventy-three consecutive patients who underwent an aortic root and ascending aorta replacement with composite valve button Bentall or flanged Bentall technique, from January 2007 to November 2018, were included in this retrospective study.

Results

Postoperative left ventricular ejection fraction significantly increased (52.14±11.38 vs. 56.79±11.36; P=0.041), left ventricular end-systolic diameter significantly reduced (38.25±9.31 mm vs. 34.17±9.15 mm; P=0.027), left ventricular end-diastolic diameter significantly reduced (56.42±9.72 mm vs. 51.58±9.03 mm; P=0.01), and left atrial diameter significantly reduced (45.33±12.77 mm vs. 39.25±12.41 mm; P=0.01), compared to preoperative values. Our long-term survival results are comparable with previous studies in which survival rates in 5 years and 10 years were 83.5% and 69.8%, respectively. In comparing patients according to their New York Heart Association (NYHA) functional class, it was shown that their postoperative functional capacity was improved during the follow-up period (2.1±0.56 vs. 1.2±0.42; P=0.001).

Conclusion

The Bentall procedure significantly improved the left ventricular systolic function and condition and decreased the left ventricular end-systolic and end-diastolic diameters and the left atrial diameter on long-term follow-up, based on the transthoracic echocardiography. Bentall procedure can be performed with acceptable mortality and morbidity rates on long-term follow-up.

The Relationship between Left Ventricular Function Indices in Tissue Doppler Imaging and Exaggerated Blood Pressure Response During the Exercise Stress Test

Background:

Studies have indicated that exaggerated hypertension during activity and stress can be a good predictor of the incidence of hypertension. This study tries to evaluate left ventricular (LV) function by tissue Doppler to assess early changes in ventricular compliance before the onset of Hypertension (HTN) in patients with exaggerated blood pressure response during the exercise test.

Materials and Methods:

In this case-control study, 40 patients without a history of hypertension with systolic blood pressure less than 140/90 which referred for exercise test, were included. The exercise test was performed for all patients. Patients who had exaggerated blood pressure during the stress test were considered as cases and the controls with normal blood pressure responses. Then standard echocardiography and Tissue Doppler imaging performed and indices of LV systolic and diastolic were recorded.

Results:

The LV mass in cases and controls were 174.9±50.78 and 152.9±33.59, respectively (P=0.114), and LV mass index in cases and controls were 127.4±13.5 and 79.8±15.75, respectively (P=0.023). Moreover, the LV Myocardial Performance Index were 0.68±0.11 and 0.48±0.06 in cases and controls, respectively (P<0.001). The heart rate, E/A, EE, E Velocity and S velocity were measuremented. Except E/A (P=0.009), there was no significant difference between the other variables measured between the cases and controls (P>0.05).

Conclusion:

The results of this study showed that using 2D conventional echocardiography as a noninvasive method if performed in prestigious centers can evaluate systolic and diastolic function Tissue Doppler parameters very well in the early stages of heart disease caused by HTN.

The Effect of High-Dose Vitamin C on Biochemical Markers of Myocardial Injury in Coronary Artery Bypass Surgery

OBJECTIVE

To evaluate the effect of high-dose vitamin C on cardiac reperfusion injury and plasma levels of creatine kinase-muscle/brain (CK-MB), troponin I, and lactate dehydrogenase (LDH) in patients undergoing coronary artery bypass grafting (CABG).

METHODS

This is a double-blind randomized clinical trial study. Fifty patients (50-80 years old) who had CABG surgery were selected. The intervention group received 5 g of intravenous vitamin C before anesthesia induction and 5 g of vitamin C in cardioplegic solution. The control group received the same amount of placebo (normal saline). Arterial blood samples were taken to determine the serum levels of CK-MB, troponin I, and LDH enzymes. Left ventricular ejection fraction was measured and hemodynamic parameters were recorded at intervals.

RESULTS

High doses of vitamin C in the treatment group led to improvement of ventricular function (ejection fraction [EF]) and low Intensive Care Unit (ICU) stay. The cardiac enzymes level in the vitamin C group was lower than in the control group. These changes were not significant between the groups in different time intervals (anesthesia induction, end of bypass, 6 h after surgery, and 24 h after surgery) for CK-MB, LDH, and troponin I. Hemodynamic parameters, hematocrit, potassium, urinary output, blood transfusion, arrhythmia, and inotropic support showed no significant difference between the groups.

CONCLUSION

Vitamin C has significantly improved the patients' ventricular function (EF) 72 h after surgery and reduced the length of ICU stay. No significant changes in cardiac biomarkers, including CK-MB, troponin I, and LDH, were seen over time in each group.

IRCT CODE

IRCT2016053019470N33.

Detection of Early Right Ventricular Dysfunction in Young Patients With Thalassemia Major Using Tissue Doppler Imaging

Background

Myocardial iron overload is the most common cause of mortality in patients with thalassemia major (TM), also known as beta-thalassemia. T2* cardiovascular magnetic resonance imaging (MRI) is the best way of monitoring cardiac iron, and new echocardiographic techniques can be used to assess cardiac function.

Objectives

The aim of this study was to assess the systolic and diastolic right ventricular (RV) function of patients with TM using tissue Doppler imaging (TDI) and to determine whether this echocardiographic technique is an adequate diagnostic tool for the screening and detection of subclinical cardiac dysfunction.

Patients and Methods

Eighty-four patients with TM were evaluated by conventional echocardiography and pulse-wave TDI. The data of the TM group (Group 1) were compared with that of 85 age- and sex-matched healthy controls (Group 2). Cardiovascular T2* MRI examinations were performed in 49 of the 85 patients.

Results

The patients with TM had significantly lower values for weight, height, body mass index, systolic arterial pressure, deceleration time, E’/A’, and ejection time (ET) than the controls. Group 1 also had significantly higher values for peak early diastolic velocity (E) over peak late diastolic velocity (A), peak early diastolic velocity of TDI (E’), peak late diastolic velocity of TDI (A’), E/E’, isovolumetric relaxation time, isovolumetric contraction time, and RV magnetic perfusion imaging (MPI) than Group 2.

Conclusions

RV diastolic dysfunction occurs before systolic deterioration in patients with TM and cannot be screened with conventional echocardiographic techniques. In routine practice, TDI measurements, MPI (for global function) and the E/E’ parameter (for diastolic function) can be used to screen and detect early RV dysfunction.

Radial left ventricular dyssynchrony by speckle tracking in apical versus non apical right ventricular pacing- evidence of dyssynchrony on medium term follow up

INTRODUCTION

To study effects of various sites of right ventricular pacing lead implantation on left ventricular function by 2-dimensional (2D) speckle tracking for radial strain and LV dyssynchrony.

METHODS

This was retrospective prospective study. Fifteen patients each with right ventricular (RV) apical (RV apex and apical septum) and non-apical (mid septal and low right ventricular outflow tract [RVOT]) were programmed to obtain 100% ventricular pacing for evaluation by echo. Location and orientation of lead tip was noted and archived by fluoroscopy. Electrocardiography (ECG) was archived and 2D echo radial dyssynchrony was calculated.

RESULTS

The baseline data was similar between two groups. Intraventricular dyssynchrony was significantly more in apical location as compared to non-apical location (radial dyssynchrony: 108.2 ± 50.2 vs. 50.5 ± 24, P < 0.001; septal to posterior wall delay [SLWD] 63.5 ± 27.5 vs. 34 ± 10.7, P < 0.001, SPWD 112.5 ± 58.1 vs. 62.7 ± 12.1, P = 0.003). The left ventricular ejection fraction was decreased more in apical location than non apical location. Interventricular dyssynchrony was more in apical group but was not statistically significant. The QRS duration, QTc and lead thresholds were higher in apical group but not statistically significant.

CONCLUSION

Pacing in non apical location (RV mid septum or low RVOT) is associated with less dyssynchrony by specific measures like 2D radial strain and correlates with better ventricular function in long term.

Novel 24-h ovine model of brain death to study the profile of the endothelin axis during cardiopulmonary injury

BACKGROUND

Upregulation of the endothelin axis has been observed in pulmonary tissue after brain death, contributing to primary graft dysfunction and ischaemia reperfusion injury. The current study aimed to develop a novel, 24-h, clinically relevant, ovine model of brain death to investigate the profile of the endothelin axis during brain death-associated cardiopulmonary injury. We hypothesised that brain death in sheep would also result in demonstrable injury to other transplantable organs.

METHODS

Twelve merino cross ewes were randomised into two groups. Following induction of general anaesthesia and placement of invasive monitoring, brain death was induced in six animals by inflation of an extradural catheter. All animals were supported in an intensive care unit environment for 24 h. Animal management reflected current human donor management, including administration of vasopressors, inotropes and hormone resuscitation therapy. Activation of the endothelin axis and transplantable organ injury were assessed using ELISA, immunohistochemistry and standard biochemical markers.

RESULTS

All animals were successfully supported for 24 h. ELISA suggested early endothelin-1 and big endothelin-1 release, peaking 1 and 6 h after BD, respectively, but there was no difference at 24 h. Immunohistochemistry confirmed the presence of the endothelin axis in pulmonary tissue. Brain dead animals demonstrated tachycardia and hypertension, followed by haemodynamic collapse, typified by a reduction in systemic vascular resistance to 46 ± 1 % of baseline. Mean pulmonary artery pressure rose to 186 ± 20 % of baseline at induction and remained elevated throughout the protocol, reaching 25 ± 2.2 mmHg at 24 h. Right ventricular stroke work increased 25.9 % above baseline by 24 h. Systemic markers of cardiac and hepatocellular injury were significantly elevated, with no evidence of renal dysfunction.

CONCLUSIONS

This novel, clinically relevant, ovine model of brain death demonstrated that increased pulmonary artery pressures are observed after brain death. This may contribute to right ventricular dysfunction and pulmonary injury. The development of this model will allow for further investigation of therapeutic strategies to minimise the deleterious effects of brain death on potentially transplantable organs.

Ventricular asystole due to inhibition of ventricular backup pacing by a dual chamber pacemaker: possible pitfalls of default settings

A 62-year-old patient presented with dizzy spells after her dual chamber pacemaker (Medtronic Enrhythm P1501DR), implanted for complete AV block, had been reprogrammed to deliver antitachycardia therapy (ATP) for paroxysmal atrial tachycardia. Her symptoms were caused by inhibition of ventricular backup pacing during ATP, leading to ventricular asystoles. Inhibition was the result of premature ventricular beats occurring prior to ATP: when ventricular backup pacing is left in the default setting, this pacemaker withholds backup pacing if any of the four preceding events is a sensed event. This case illustrates the possibly hazardous effects of default pacemaker settings, especially in pacemaker-dependent patients. (Neth Heart J 2010;18:323-6.).