Restoration of optimal left ventricular apical geometry and rotation following surgical ventricular restoration using rectangular patch plasty technique: a pilot study using cardiac magnetic resonance

Clinical and hemodynamic outcomes of the Dor procedure in adults with ischemic cardiomyopathy

Ischemic cardiomyopathy continues to be a major contributor to congestive heart failure, which places a significant burden on our healthcare system. Improving medications and different coronary revascularization strategies are the mainstays in the management of ischemic cardiomyopathy. Although medications and mechanical circulatory support are playing an ever-increasing role, cardiac transplantation remains the gold standard for treating advanced heart failure. Given the small number of available and suitable donor hearts, transplantation is limited for the majority of patients. Surgical ventricular restoration has repeatedly been suggested as a viable alternative in managing heart failure in select patients, as it is believed that surgically returning the ventricle to its original dimensions is possible and associated with favorable outcomes. The purpose of this manuscript is to comprehensively review the current literature on various surgical strategies for ventricular restoration. We also contextualize the published data with respect to ventricular function, volume, structure, arrhythmias, mitral regurgitation, and clinical outcomes.

Surgical ventricular restoration-meta-analysis of observational studies

Background

Technique of surgical ventricular restoration (SVR) may impact its outcomes. Therefore, we conducted a meta-analysis of studies on SVR performed by using different techniques and studied outcomes.

Methods

Scientific databases were searched for studies on SVR. End points assessed were NYHA class, left ventricular ejection fraction (LVEF), end-systolic volume index (ESVI), sphericity index, apical rotations, mortality, and re-admissions for heart failure.

Results

Circular patch use showed significant increases in LVEF by 9.53% (7.62, 11.45), decreases in ESVI by - 35.16 ml (- 44.97, - 25.34), improvements in NYHA class by - 1.29 (- 1.45, - 1.13), and decreases in sphericity index by - 0.04 (- 0.08, 0.00) . In studies using rectangular patch, the LVEF showed an increase by 5.75% (3.52, 7.98,), the NYHA class improved by - 2.45 (- 2.59, - 2.32). The decrease in ESVI was - 40.36 ml (- 62.2, - 18.52). The apical rotation increased by 3.45 ⁰ (0.62, 6.29,). Re-admission for heart failure and mortality was less.When the magnitude of ESVI decrease were compared within studies using rectangular patch, the greatest decrease in ESVI was notedwith use of a rectangular patch. (- 59 ml versus - 40 ml a very narrow patch and - 22 ml use of oval patch) The improvements in sphericity index at 2 years in use of rectangular patch study was - 0.78 ± 0.11 versus 0.00 ± 0.03 in use of oval patch study.

Conclusions

Rectangular patch use resulted in maximal decreases in ESVI and sphericity index. Mortality and re-admissions for heart failure were also significantly less at mid-term after SVR.

Tailoring therapy for ischemic cardiomyopathy: is Laplace's law enough?

The burden of heart failure has long plagued the productive years of the population, with therapeutic advances in the timely treatment of ischemic heart disease decreasing its associated mortality. Angiotensin-converting enzyme inhibitors and β-blockers have impacted heart failure therapeutics in a revolutionary way. The importance of blockade of the renin-angiotensin system and adrenergic stimulation are fully accepted concepts that apply in young and old, symptomatic and asymptomatic, borderline low and very low Ejection Fraction (EF), left ventricular failure and biventricular failure. Despite several interventions, both pharmaceutical and device based for the treatment of ensuing heart failure, the incidence is increasing in large proportions. Newer molecules like sacubitril show more promise. Despite these novel therapies, several patients relentlessly progress to a stage of advanced heart failure. The use of left-ventricular-assist devices has variable clinical benefit, with some patients progressing to heart transplantation.

cMRI-BED: A novel informatics framework for cardiac MRI biomarker extraction and discovery applied to pediatric cardiomyopathy classification

Background

Pediatric cardiomyopathies are a rare, yet heterogeneous group of pathologies of the myocardium that are routinely examined clinically using Cardiovascular Magnetic Resonance Imaging (cMRI). This gold standard powerful non-invasive tool yields high resolution temporal images that characterize myocardial tissue. The complexities associated with the annotation of images and extraction of markers, necessitate the development of efficient workflows to acquire, manage and transform this data into actionable knowledge for patient care to reduce mortality and morbidity.

Methods

We develop and test a novel informatics framework called cMRI-BED for biomarker extraction and discovery from such complex pediatric cMRI data that includes the use of a suite of tools for image processing, marker extraction and predictive modeling. We applied our workflow to obtain and analyze a dataset of 83 de-identified cases and controls containing cMRI-derived biomarkers for classifying positive versus negative findings of cardiomyopathy in children. Bayesian rule learning (BRL) methods were applied to derive understandable models in the form of propositional rules with posterior probabilities pertaining to their validity. Popular machine learning methods in the WEKA data mining toolkit were applied using default parameters to assess cross-validation performance of this dataset using accuracy and percentage area under ROC curve (AUC) measures.

Results

The best 10-fold cross validation predictive performance obtained on this cMRI-derived biomarker dataset was 80.72% accuracy and 79.6% AUC by a BRL decision tree model, which is promising from this type of rare data. Moreover, we were able to verify that mycocardial delayed enhancement (MDE) status, which is known to be an important qualitative factor in the classification of cardiomyopathies, is picked up by our rule models as an important variable for prediction.

Conclusions

Preliminary results show the feasibility of our framework for processing such data while also yielding actionable predictive classification rules that can augment knowledge conveyed in cardiac radiology outcome reports. Interactions between MDE status and other cMRI parameters that are depicted in our rules warrant further investigation and validation. Predictive rules learned from cMRI data to classify positive and negative findings of cardiomyopathy can enhance scientific understanding of the underlying interactions among imaging-derived parameters.