Right-sided heart failure: Diagnosis and treatment strategies

Epidemiology, Risk Factors, and Outcome of Cardiac Dysrhythmias in a Noncardiac Intensive Care Unit

Introduction

Several extrinsic factors contribute to the development of cardiac dysrhythmias. In intensive care unit (ICU) settings and among critically ill patients who are exposed to a large number of risk factors, cardiac disturbances are more common.

Objectives

This study aimed to examine the epidemiology, risk factors, and outcome of cardiac dysrhythmias in a non-cardiac ICU.

Methods

This is a retrospective, single-center, observational study conducted in a tertiary noncardiac ICU at Imam Khomeini Hospital in Ahvaz, Iran. Out of the 360 adult patients aged 18 years and older who were admitted to ICU for longer than 24 h, 340 cases who met the study inclusion criteria were recruited between March 2018 until October 2018.

Results

The most common nonsinus dysrhythmias were new-onset atrial fibrillation (NOAF) (12.9%) and ventricular tachycardia (21 patients—6.2%). According to our results, previous percutaneous coronary instrumentation, acute kidney injury, sepsis, and hyperkalemia act as risk factors in the development of cardiac dysrhythmias. Additionally, we found out that thyroid dysfunction and pneumonia can predict the development of NOAF in critically ill patients. The estimated mortality rate among patients with NOAF in this study was 15.7% (p < .05).

Conclusion

Cardiac dysrhythmias are common in ICU patients and treating the risk factors can help to prevent their development and improve patient management and outcome.

Isolated Subclinical Right Ventricle Systolic Dysfunction in Patients after Liver Transplantation

Although hemodynamic alterations in end-stage liver disease (ESLD) and its association with porto-pulmonary hypertension have been well-established, the long-term effects of ESLD on RV systolic function in patients without porto-pulmonary hypertension remain disregarded. Here we aimed to assess the long-term effect of ESLD on RV function and its relationship with the use of NSBBs and clinical, laboratory and imaging parameters in end-stage liver disease. The use of NSBBs is still controversial due to concerns about reduced cardiac contractility and the possibility of increased mortality. Thirty-four liver transplant recipients were included. Demographic characteristics, laboratory and baseline echocardiography measures were obtained. Patients were recalled for transthoracic echocardiographic evaluation after transplantation. Right ventricle dysfunction was identified by having at least one value below the reference levels of RV S’, or TAPSE. Isolated subclinical RV dysfunction was observed at 20.6% of the sample population. The present study demonstrates hemodynamic circulation in cirrhosis and increased preload and afterload might have long-term effects on RV function, even the lack of porto-pulmonary hypertension. These findings underline the significance of cardiac function follow-up in cirrhotic patients after transplantation. In this study, patients treated with propranolol seemed to have better RV function and less gastrointestinal bleeding. We speculated that preoperative propranolol treatment might help preserve RV function by providing RAS suppression, improving endothelial function and hyperdynamic circulation seen in ESLD. This potential protective relationship between the use of propranolol and RV function might improve mortality or graft-failure during OLT and after liver transplantation in patients with cirrhosis.

Atrial Fibrillation in Patients with Acute Pulmonary Embolism: Clinical Significance and Impact on Prognosis

Pulmonary embolism (PE) is one of the most common causes of cardiovascular death. The most often PE etiology is a deep vein thrombosis (DVT) of the lower extremities, but embolic material can arise in pelvic or upper extremity veins as well as in right heart chambers. There is growing number of evidences of atrial fibrillation (AF) involvement in PE. The presence of AF in patients with PE may be both the cause and the consequence of PE. The PE association with AF should be considered in patients without confirmed DVT and with history of AF, which itself is associated with prothrombotic state. The valuable diagnostic method is echocardiography that may bring the insight into source of embolic material. Another possible AF and PE association is the AF as a consequence of an abrupt increase in pulmonary vascular resistance due to the occlusion of the pulmonary vessels. Large-scale population-based studies have provided a considerable body of evidence on the involvement of PE in the onset of subsequent AF. Another important issue is the influence of AF on prognosis in patients with PE. Most investigators demonstrated a negative impact of AF on mortality. The main problem to resolve is whether AF is an independent mortality risk factor or whether it occurs as a result of comorbidities or the severity of a PE episode. Although the pathophysiological basis of this bidirectional relationship exists, many questions are still unresolved and require further studies, including the significance of paroxysmal AF accompanying an acute PE episode, the usefulness of PE risk scales in patients with concomitant AF, and the effect of anticoagulant treatment on PE and AF occurrence. Regardless of the type of AF, clinicians should be alert to the possibility of PE in patients with previous history of AF or presenting with new-onset AF.

Three-Dimensional Tricuspid Annular Motion Analysis from Cardiac Magnetic Resonance Feature-Tracking

Right ventricular (RV) dysfunction is known to be highly correlated with mortality and morbidity; nevertheless, imaging-based assessment of RV anatomy and physiology lags far behind that of the left ventricle. In this study, we advance RV imaging using cardiac magnetic resonance (CMR) to accomplish the following aims: (i) track the motion of six tricuspid annular (TA) sites using a semi-automatic tracking system; (ii) extract clinically important TA measurements-systolic velocity (Sm), early diastolic velocity (Em), late diastolic velocity (Am), and TA plane systolic excursion (TAPSE)-for each TA site and compare these CMR-derived measurements in healthy subjects vs. patients with heart failure, repaired tetralogy of Fallot, pulmonary hypertension, and hypertrophic cardiomyopathy; (iii) investigate how the TA motion related measurements compare with information provided by invasive right heart catheterization (RHC); (iv) evaluate the rate of change in surface area swept out by the reconstructed tricuspid annulus over time and (v) assess the reproducibility of this CMR-based technique. Results indicate that TA motion parameter data obtained in three dimensions using the proposed CMR-based systematic methodology achieve superior diagnostic performance (Sm: AUC = 0.957; TAPSE: AUC = 0.981) compared to two-dimensional CMR imaging. Both Sm and TAPSE from CMR correlated positively with dP/dt _max/IP from RHC (Sm: r = 0.621, p < 0.01; TAPSE: r = 0.648, p < 0.01). Our highly reproducible and robust methodology holds potential for extending CMR imaging to characterization of TA morphology and dynamic behaviour, eventually leading to deeper understanding of RV function and improved diagnostic capability.

An Algorithm for the Segmentation of Highly Abnormal Hearts Using a Generic Statistical Shape Model

Statistical shape models (SSMs) have been widely employed in cardiac image segmentation. However, in conditions that induce severe shape abnormality and remodeling, such as in the case of pulmonary hypertension (PH) or hypertrophic cardiomyopathy (HCM), a single SSM is rarely capable of capturing the anatomical variability in the extremes of the distribution. This work presents a new algorithm for the segmentation of severely abnormal hearts. The algorithm is highly flexible, as it does not require a priori knowledge of the involved pathology or any specific parameter tuning to be applied to the cardiac image under analysis. The fundamental idea is to approximate the gross effect of the abnormality with a virtual remodeling transformation between the patient-specific geometry and the average shape of the reference model (e.g., average normal morphology). To define this mapping, a set of landmark points are automatically identified during boundary point search, by estimating the reliability of the candidate points. With the obtained transformation, the feature points extracted from the patient image volume are then projected onto the space of the reference SSM, where the model is used to effectively constrain and guide the segmentation process. The extracted shape in the reference space is finally propagated back to the original image of the abnormal heart to obtain the final segmentation. Detailed validation with patients diagnosed with PH and HCM shows the robustness and flexibility of the technique for the segmentation of highly abnormal hearts of different pathologies.

Automatic cardiac segmentation using semantic information from random forests

We propose a fully automated method for segmenting the cardiac right ventricle (RV) from magnetic resonance (MR) images. Given a MR test image, it is first oversegmented into superpixels and each superpixel is analyzed to detect the presence of RV regions using random forest (RF) classifiers. The superpixels containing RV regions constitute the region of interest (ROI) which is used to segment the actual RV. Probability maps are generated for each ROI pixel using a second set of RF classifiers which give the probabilities of each pixel belonging to RV or background. The negative log-likelihood of these maps are used as penalty costs in a graph cut segmentation framework. Low-level features like intensity statistics, texture anisotropy and curvature asymmetry, and high level context features are used at different stages. Smoothness constraints are imposed based on semantic information (importance of each feature to the classification task) derived from the second set of learned RF classifiers. Experimental results show that compared to conventional method our algorithm achieves superior performance due to the inclusion of semantic knowledge and context information.

Active shape model with inter-profile modeling paradigm for cardiac right ventricle segmentation

In this work, a novel active shape model (ASM) paradigm is proposed to segment the right ventricle (RV) in cardiac magnetic resonance image sequences. The proposed paradigm includes modifications to two fundamental steps in the ASM algorithm. The first modification includes employing the 2D-principal component analysis (PCA) to capture the inter-profile relations among shape's neighboring landmarks and then model the inter-profile variations between the training set. The second modification is based on using a multi-stage searching algorithm to find the best profile match based on the best maintained profile's relations and thus the best shape fitting in an iterative manner. The developed methods are validated using a database of short axis cine bright blood MRI images for 30 subjects with total of 90 images. Our results show that the segmentation error can be reduced by about 0.4 mm and contour overlap increased by about 4% compared to the classical ASM technique with paired Student's t-test indicates statistical significance to a high degree for our results. Furthermore, comparison with literature shows that the proposed method decreases the RV segmentation error significantly.

Review of Movahed's sign (D shaped left ventricle seen on gated SPECT) suggestive of right ventricular overload

Recently, D shaped ventricle seen on gated SPECT imaging (Movahed's sign) has shown to correlate with right ventricular overload similar to the D shape ventricle seen on echocardiography. Right ventricle (RV) imaging during gated SPECT studies is challenging because of the low tracer uptake due to relatively smaller right ventricular myocardial mass and lower coronary flow to the RV. Increased mass or workload causes higher tracer uptake in the RV wall secondary to increase in RV wall thickness and higher coronary flow. Furthermore, increased RV volume or pressure load can cause displacement of the septum towards the left ventricle causing septal flattening and a D shaped configuration of the left ventricular septum. This is an important finding that should be a part of nuclear gated SPECT interpretation.

Plasma CCN2/connective tissue growth factor is associated with right ventricular dysfunction in patients with neuroendocrine tumors

BACKGROUND

Carcinoid heart disease, a known complication of neuroendocrine tumors, is characterized by right heart fibrotic lesions. Carcinoid heart disease has traditionally been defined by the degree of valvular involvement. Right ventricular (RV) dysfunction due to mural involvement may also be a manifestation. Connective tissue growth factor (CCN2) is elevated in many fibrotic disorders. Its role in carcinoid heart disease is unknown. We sought to investigate the relationship between plasma CCN2 and valvular and mural involvement in carcinoid heart disease.

METHODS

Echocardiography was performed in 69 patients with neuroendocrine tumors. RV function was assessed using tissue Doppler analysis of myocardial systolic strain. Plasma CCN2 was analyzed using an enzyme-linked immunosorbent assay. Mann-Whitney U, Kruskal-Wallis, Chi-squared and Fisher's exact tests were used to compare groups where appropriate. Linear regression was used to evaluate correlation.

RESULTS

Mean strain was -21% +/- 5. Thirty-three patients had reduced RV function (strain > -20%, mean -16% +/- 3). Of these, 8 had no or minimal tricuspid and/or pulmonary regurgitation (TR/PR). Thirty-six patients had normal or mildly reduced RV function (strain < or = -20%, mean -25% +/- 3). There was a significant inverse correlation between RV function and plasma CCN2 levels (r = 0.47, p < 0.001). Patients with reduced RV function had higher plasma CCN2 levels than those with normal or mildly reduced RV function (p < 0.001). Plasma CCN2 > or = 77 microg/L was an independent predictor of reduced RV function (odds ratio 15.36 [95% CI 4.15;56.86]) and had 88% sensitivity and 69% specificity for its detection (p < 0.001). Plasma CCN2 was elevated in patients with mild or greater TR/PR compared to those with no or minimal TR/PR (p = 0.008), with the highest levels seen in moderate to severe TR/PR (p = 0.03).

CONCLUSIONS

Elevated plasma CCN2 levels are associated with RV dysfunction and valvular regurgitation in NET patients. CCN2 may play a role in neuroendocrine tumor-related cardiac fibrosis and may serve as a marker of its earliest stages.

Assessment of the right ventricle by echocardiography: a primer for cardiac sonographers

The assessment of right ventricular (RV) structure and function by echocardiography has been improved by advancements that include Doppler tissue imaging, strain imaging, and three-dimensional imaging. Doppler tissue imaging and strain imaging can be useful for the assessment of regional RV systolic and diastolic function. Three-dimensional imaging has been reported to determine RV volumes and ejection fraction, which have previously been cumbersome to measure with conventional two-dimensional echocardiography. This article addresses the role of conventional and newer methods of echocardiography to assist sonographers in understanding the technical considerations, limitations, and pitfalls of image acquisition and analysis of RV structure and function.