Low-Power Long-Duration Versus High-Power Short-Duration Radiofrequency Ablation of the Atrioventricular Node.

BACKGROUND: Atrioventricular node (AVN) radiofrequency (RF) ablation is a highly effective treatment of atrial tachyarrhythmias that are resistant to other management modalities. To date, there is limited research that compares the properties of different RF ablation catheters. The current study aims to compare the effectiveness of several types of RF catheters in AVN ablation. METHODS: 66 patients, with a mean age of 73.27 years, underwent AVN RF ablation. The catheters used were categorized as: un-irrigated (UI), externally-irrigated (EI), and contact force-sensing with 10-20 grams of force. EI catheters were divided into two different settings: low-power long-duration (LPLD) (30W, 45°C, and 60 sec) and high-power short-duration (HPSD) (50W, 43°C, and 12 sec). We compared the success rate of the different RF catheters using logistic regression and lesion times using linear regression. RESULTS: The distribution of the types of catheters used is: UI in 48%, LPLD in 16%, and HPSD in 36% of patients. All ablation procedures were successful, with no immediate post-procedure complications. HPSD had a significantly shorter lesion time than UI catheters by 403.42 sec [-631.67, -175.17]. CONCLUSION: UI catheters, LPLD, and HPSD were equally safe and effective in ablation procedures. The HPSD catheter had a significantly shorter lesion time and, thus, overall decreased procedure time.

Decompensated Heart Failure as the Initial Presentation of Multiple Myeloma: A Case Report.

Amyloid deposition in the setting of multiple myeloma (MM) is a well-documented phenomenon. In this paper, we present the rare case of a 62-year-old male who presented with decompensated heart failure in the setting of cardiac amyloid deposition as the initial presentation of MM. The patient presented to the emergency department with two weeks of worsening lower extremity edema. Laboratory exam revealed elevated troponin I, elevated B-type natriuretic peptide (BNP), macrocytosis, increased urine protein/creatinine ratio, and a monoclonal peak on both serum protein electrophoresis (SPEP) and urine protein electrophoresis (UPEP). Transthoracic echocardiogram (TTE) revealed findings suggestive of amyloidosis. Abdominal fat pad biopsy confirmed amyloid deposition. The patient did not have other symptoms typically seen in multiple myeloma, such as fatigue or weakness, bone pain, or weight loss. In conclusion, we present a rare case of decompensated heart failure in the setting of amyloidosis as the initial presentation of multiple myeloma.

A Case of Papillary Fibroelastoma of the Aortic Valve Causing an Embolic Ischemic Stroke.

Papillary fibroelastomas (PFEs) are the second most common primary cardiac tumors after myxomas. They are typically located on the aortic valve and comprise a short pedicle with multiple papillary fronds. PFEs are benign but highly friable in nature. Patients can be asymptomatic or present with severe thromboembolic complications. Echocardiography is the modality of choice for the diagnosis of these masses and surgical resection is indicated even in asymptomatic patients. Here, we have presented a case of a 53-year-old male who presented with a stroke after embolization of a PFE.

A Complete Workup of Recurrent Syncope Caused by Significant Left Main Coronary Artery Stenosis.

Syncope is usually caused by cerebral hypoperfusion. Differentials to consider during the workup of syncope includes vasovagal, orthostatic, drug-induced, arrhythmia, structural heart disease, and ischemic cardiomyopathy.  An 81-year-old African American man with recurrent witnessed syncopal events and newly diagnosed heart failure underwent extensive cardiac workup including electrocardiograms (EKG), echocardiogram, Holter monitor, electrophysiology (EP) study, and coronary angiogram. The workup revealed ischemic ventricular tachycardia in the setting of significant coronary artery disease including 80% distal left main disease. The patient underwent a coronary artery bypass graft (CABG) with subsequent resolution of further syncopal events. The patient was successfully discharged with guideline-directed medical therapy for heart failure with reduced ejection fraction (HFrEF) and coronary artery disease (CAD).  It is very rare for ischemic cardiomyopathy to present as syncope; however, it is not unheard of. Extensive transmural ischemia could lead to ventricular arrhythmias, a known cause of syncope. This rare presentation serves as a reminder to consider ischemic heart disease in the evaluation of syncope.

Mitral Leaflet Flail as a Late Complication of Infective Endocarditis: A Case Report.

Infective Endocarditis (IE) refers to an infection of the endocardial surface of the heart which leads to a wide array of complications, including heart failure, perivalvular abscess, metastatic infection, septic embolization, mycotic aneurysms, neurological and renal complications. Mitral leaflet flail (MLF), defined as a failure of leaflet coaptation with the rapid systolic movement of the involved leaflet into the left atrium, is a rare complication of IE which can lead to severe mitral regurgitation. Echocardiography plays a key role in making its diagnosis with transesophageal echocardiograms (TEE), providing greater sensitivity and specificity compared to transthoracic echocardiograms (TTE). MLF is often misdiagnosed, or diagnosis is delayed due to its presentation with non-specific cardiac symptoms. However, early diagnosis with echocardiography and prompt surgical correction leads to improved long-term survival. Here we have presented a case of a 71-year-old female with a past medical history of IE nine years ago who was referred to the cardiology clinic for one month of exertional dyspnea. TTE showed severe mitral regurgitation, and subsequent TEE confirmed flail mitral leaflet.

A Rare Case of Dilated Cardiomyopathy, Focal Segmental Glomerulosclerosis, and Bell's Palsy in a 29-Year-Old Male After Coxsackievirus Infection.

Dilated cardiomyopathy (DCM) is a severe myocardial disease with diversified etiologies. Coxsackievirus serotype B (CV-B) is a known cause of infectious myocarditis that leads to DCM. The pathogenesis of CV-B myocarditis is complex and involves a combination of tissue destruction from viral proliferation and host immune response. Diagnosis is based on clinical findings and the presence of post-infection elevated titers of IgM antibodies to CV-B. Echocardiography is an important imaging modality that plays a key role in diagnosing DCM. Rare complications of coxsackievirus infection may include facial paralysis and chronic kidney disease with nephrotic syndrome. Here we present a rare case of a 29-year-old-male with recent Bell's palsy who presented with new-onset heart failure with left ventricular ejection fraction of 5% and focal segmental glomerulosclerosis nephrotic syndrome in the setting of elevated antibodies to CV-B.

Staphylococcus lugdunensis Infectious Endocarditis Complicated by Embolic Stroke After Colonoscopy in a 58-Year-Old Female.

There are a significant number of colonoscopies and esophagogastroduodenoscopies (EGDs) done in the United States every year and post-endoscopic infections are frequently seen. Data demonstrating causality between endoscopic procedures and infectious endocarditis (IE) or that antibiotic prophylaxis prior to endoscopic procedures protects against IE is still lacking. Here we have presented the case of a patient who underwent diagnostic colonoscopy as part of a malignancy workup and was later found to be septic with Staphylococcus lugdunensis bacteremia and had IE. We hypothesized that the infection was most likely contracted during colonoscopy as a result of bacterial translocation from the perineal region to the bloodstream. This case report highlights the need for further studies investigating the efficacy of prophylactic antibiotics in reducing the risk of IE after colonoscopies.

Heart failure with preserved ejection fraction update: A review of clinical trials and new therapeutic considerations.

Between 2013 and 2016 there were approximately 6.2 million adults in the United States living with heart failure; nearly half had an ejection fraction that was preserved. Despite the high prevalence of heart failure with preserved ejection fraction (HFpEF), our understanding of this disease is limited and it still carries significant morbidity and mortality worldwide. At present, physicians are burdened by the inconclusive benefits of currently available treatment options. Recently the scientific community has seen an influx of new pathophysiology studies and outcome trials that have reshaped our understanding of HFpEF as a complex, multi-systemic disease. Pharmacological trials involving beta-blockers, angiotensin II receptor antagonists, aldosterone antagonists, and angiotensin-neprilysin inhibitors have demonstrated encouraging results, but have yet to reach the significance of advancements made in the treatment of heart failure with reduced ejection fraction. This review aims to summarize landmark clinical trials that have influenced current treatment guidelines, and reports on emerging evidence supporting/refuting new treatment modalities including pharmacotherapy, lifestyle modification and device therapy.

Mysterious Left Atrial Mass in a Patient With Metastatic Prostate Cancer.

Cardiac tumors (CTs) are a rare group of disorders that encompass a broad set of masses. They are subclassified into neoplastic and non-neoplastic lesions. Neoplastic lesions can be further subdivided into either primary cardiac tumors (PCTs) or secondary cardiac tumors (SCTs) which are metastasis to the heart. Cardiac myxomas are the most common pathological type of benign PCT followed by rhabdomyomas, papillary fibroelastomas, fibromas, lipomas, and leiomyomas. Here, we present a case of a patient with left atrial mass in the setting of stage IV prostate cancer. We have used transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) for characterization and differential generation. Our findings are presented in high-quality imaging and video and our top differentials include PCT, thrombi, and metastasis. Although a full diagnostic workup was not completed due to limitations in diagnostic tests available, metastasis to the heart could not be excluded due to the high staging and extensive sclerotic involvement of this malignancy. We emphasized the importance of multimodality imaging, e.g., TTE, TEE, cardiac magnetic resonance (CMR), and cardiac computed tomography (CT) in the workup of incidental cardiac masses and differential refinement.

A Network-Centric Framework for the Evaluation of Mutual Exclusivity Tests on Cancer Drivers.

One of the key concepts employed in cancer driver gene identification is that of mutual exclusivity (ME); a driver mutation is less likely to occur in case of an earlier mutation that has common functionality in the same molecular pathway. Several ME tests have been proposed recently, however the current protocols to evaluate ME tests have two main limitations. Firstly the evaluations are mostly with respect to simulated data and secondly the evaluation metrics lack a network-centric view. The latter is especially crucial as the notion of common functionality can be achieved through searching for interaction patterns in relevant networks. We propose a network-centric framework to evaluate the pairwise significances found by statistical ME tests. It has three main components. The first component consists of metrics employed in the network-centric ME evaluations. Such metrics are designed so that network knowledge and the reference set of known cancer genes are incorporated in ME evaluations under a careful definition of proper control groups. The other two components are designed as further mechanisms to avoid confounders inherent in ME detection on top of the network-centric view. To this end, our second objective is to dissect the side effects caused by mutation load artifacts where mutations driving tumor subtypes with low mutation load might be incorrectly diagnosed as mutually exclusive. Finally, as part of the third main component, the confounding issue stemming from the use of nonspecific interaction networks generated as combinations of interactions from different tissues is resolved through the creation and use of tissue-specific networks in the proposed framework. The data, the source code and useful scripts are available at: https://github.com/abu-compbio/NetCentric.

A Rare Indolent Course of Rhinocerebral Mucormycosis.

Mucormycosis is a highly invasive and rapidly progressing form of fungal infection that can be fatal. The infection usually begins after oral or nasal inhalation of fungal spores and can enter the host through a disrupted mucosa or an extraction wound. The organism becomes pathogenic when the host is in an immunocompromised state. There are several clinical presentations of mucormycosis including rhinocerebral, pulmonary, cutaneous, gastrointestinal, disseminated, and miscellaneous forms. The most common clinical presentation of mucormycosis is the rhinocerebral form which has a high predilection for patients with diabetes and metabolic acidosis. An indolent disease course taking weeks to months of this infection is rare making it difficult to diagnose. Therefore, early detection and prompt treatment with surgical and antifungal therapy are very important in achieving good treatment outcomes.

MEXCOwalk: mutual exclusion and coverage based random walk to identify cancer modules.

MOTIVATION: Genomic analyses from large cancer cohorts have revealed the mutational heterogeneity problem which hinders the identification of driver genes based only on mutation profiles. One way to tackle this problem is to incorporate the fact that genes act together in functional modules. The connectivity knowledge present in existing protein-protein interaction (PPI) networks together with mutation frequencies of genes and the mutual exclusivity of cancer mutations can be utilized to increase the accuracy of identifying cancer driver modules. RESULTS: We present a novel edge-weighted random walk-based approach that incorporates connectivity information in the form of protein-protein interactions (PPIs), mutual exclusivity and coverage to identify cancer driver modules. MEXCOwalk outperforms several state-of-the-art computational methods on TCGA pan-cancer data in terms of recovering known cancer genes, providing modules that are capable of classifying normal and tumor samples and that are enriched for mutations in specific cancer types. Furthermore, the risk scores determined with output modules can stratify patients into low-risk and high-risk groups in multiple cancer types. MEXCOwalk identifies modules containing both well-known cancer genes and putative cancer genes that are rarely mutated in the pan-cancer data. The data, the source code and useful scripts are available at: https://github.com/abu-compbio/MEXCOwalk. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.