Sudarshan Balla

Risk factors for atherosclerosis in patients with chronic kidney disease: recognition and management.

Heart disease is the most common cause of death in patients with chronic kidney disease (CKD), particularly in those receiving dialysis. Atherosclerosic cardiovascular (CV) disease (CVD) accounts for a large number of these deaths. Atherosclerosis is accelerated in patients with CKD due predominantly to the high prevalence of traditional CVD risk factors in the CKD population. CKD aggravates pre-existent traditional risk factors such as hypertension and dyslipidemia due to secondary renal parenchymal hypertension and secondary dyslipidemia. In addition, a variety of non-traditional risk factors that occur commonly in CKD patients contribute to CV risk. Recent studies suggest that CKD itself may be an independent risk factor for CVD, particularly coronary heart disease (CHD). Many therapies aimed at CV risk factor modification that have been successful in reducing CV risk in the general population are less effective or ineffective in favorably modifying CV risk in CKD.

Does Long-Term Furosemide Therapy Cause Thiamine Deficiency in Patients with Heart Failure? A Focused Review

Diuretic therapy is a cornerstone in the management of heart failure. Most studies assessing body thiamine status have reported variable degrees of thiamine deficiency in patients with heart failure, particularly those treated chronically with high doses of furosemide. Thiamine deficiency in patients with heart failure seems predominantly to be due to increased urine volume and urinary flow rate. There is also evidence that furosemide may directly inhibit thiamine uptake at the cellular level. Limited data suggest that thiamine supplementation is capable of increasing left ventricular ejection fraction and improving functional capacity in patients with heart failure and a reduced left ventricular ejection fraction who were treated with diuretics (predominantly furosemide). Therefore, it may be reasonable to provide such patients with thiamine supplementation during heart failure exacerbations.

Management of bleeding in patients receiving non-vitamin K antagonists

Anticoagulation with non-vitamin K antagonists (Non vitamin K oral anticoagulant (NOACs)) including dabigatran, rivaroxaban, apixaban and edoxaban is at least as effective as warfarin, has fewer drug and food interactions and does not require monthly monitoring. Although major bleeding with NOACs is infrequent, there remains concern about the ability to effectively treat episodes of major bleeding. New agents have been developed that are capable of providing rapid reversal of the anticoagulation effect of NOACs. Idarucizumab normalises the dilute thrombin time and the ecarin clotting time, both of which are elevated with dabigatran. Andexanet alfa reduces increased anti-factor Xa activity seen with the use of rivaroxaban and apixaban. A universal reversal agent is in development. These agents, unlike agents to reverse the anticoagulation effect of vitamin K antagonists, appear to reverse the specific NOAC anticoagulant. The development of reversal agents is a major advancement in managing bleeding in the era of NOACs. Future studies will be required to determine the impact on important clinical outcomes.

Left ventricular outflow tract and mid-cavity obstruction may cause false-positive dobutamine stress echocardiograms

Left ventricular (LV) outflow tract obstruction (LVOTO) occurs in up to 20% of patients undergoing dobutamine stress echocardiography (DSE). Mid-cavity LV obstruction occurs less commonly during DSE. LV regional wall motion abnormalities during DSE may occur despite normal coronaries due to hypertensive blood pressure response and takotsubo stress cardiomyopathy. We describe herein two cases of LVOTO and one case of mid-cavity LV obstruction during DSE associated with transient apical hypokinesis.

Systematic review of non-invasive cardiovascular imaging in the diagnosis of constrictive pericarditis

Background Diagnosis of constrictive pericarditis (CP) can be challenging. It can be nearly impossible to distinguish CP from other causes of right heart failure. Although various imaging modalities help in the diagnosis, no test is definitive. Several reviews have addressed the role of various imaging techniques in the diagnosis of CP but a systematic review has not yet been published. Objective Our intention was to study the ability of various non-invasive imaging modalities to diagnose CP in patients with surgically confirmed disease and to apply our findings to develop a clinically useful diagnostic algorithm. Methods A PubMed (NLM) search was performed with MeSH term “constrictive pericarditis”. Original articles that investigated the ability of various cardiovascular imaging modalities to noninvasively diagnose surgically confirmed CP were included in our review. Investigations that included any cases without surgical confirmation were excluded. Results The PubMed search yielded 3001 results with MeSH term “constrictive pericarditis” (January 8, 2016). We identified (40) studies on CP that matched our inclusion criteria. We summarized our results sorted by individual non-invasive CV imaging modalities – echocardiography, cardiac computed tomography (CT), and magnetic resonance imaging (MRI). Under each imaging modality, we grouped our discussion based on different parameters useful in CP diagnosis. Conclusions In conclusion, contemporary diagnosis of CP is based on clinical features and echocardiography. Cardiac MRI is recommended in patients where echocardiography is not diagnostic. Both cardiac MRI and CT can guide surgical planning but we prefer MRI as it provides both structural and functional information.

Bioabsorbable Coronary Stents - Are These the Next Big Thing in Coronary Angioplasty?

The role of percutaneous coronary intervention (PCI) in the treatment of coronary artery disease has grown at an astronomical pace. Drug eluting stents (DES) offer advantages over bare metal stents (BMS) such as reduction in early in-stent restenosis rates. However, they have disadvantages like from increased late stent thrombosis when compared with BMS. Furthermore, recent data suggest endothelial dysfunction in the DES stented segments of the arteries. Currently, bioabsorbable stents are under development to avert the complications of DES such as stent thrombosis via degradation of the stent over time. The hypothetical advantage of leaving behind a natural vessel and restoring vasoreactivity may be the almost normal physiology which can be achieved after an intervention with a stent. The ABSORB and the PROGRESS AMS are two of the recent clinical trials that have looked at the outcomes of using bioabsorbable stents. So far, data from these and other studies has yielded mixed results in terms of angiographic and clinical outcomes. Newer stents such as REVA and WHISPER are presently being tested in preclinical and clinical trials. The landscape for bioabsorbable stents is constantly evolving through continued improvisation on existing technology and emergence of new technology. Large scale randomized trials are still needed with adequate long term follow-up for safety and benefits to have mainstream application in coronary artery disease, bioabsorbable stents are a promising innovation in the field of PCI. We review some of the patents and the data that is emerging on bioabsorbable stents in addition to currently ongoing clinical trials.

Clinical outcomes of PCSK9Is: a meta-analysis of randomized clinical trials

Background Previous studies of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9Is) were not designed to detect clinical benefit and were underpowered for this outcome. However, recently published trials reported improvement in clinical outcomes. The aim of this meta-analysis to assess the impact of PCSK9Is on clinical outcomes. Methods Medline, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL) were queried from January 2000 through March 2017. Only randomized controlled trials (RCTs) comparing clinical outcomes in patients treated with PCSK9I versus control group were included. Two independent reviewers selected the studies and extracted data in duplicate. Random-effects meta-analysis was used to pool outcomes across studies. Study endpoints included: major adverse cardiovascular events (MACE), myocardial infarction (MI), stroke, coronary revascularization, cardiovascular (CV) mortality and all-cause mortality. Results A total of 62,776 patients (mean age 61 years, 73% were males) were included from six randomized clinical trials. In comparison to control group, PCSK9I use was associated with lower MACE (RR =0.81, 95% CI, 0.70-0.93, P=0.003), MI (RR =0.78, 95% CI, 0.63-0.97, P=0.03), stroke (RR =0.74, 95% CI, 0.64-0.87, P=0.0002) and coronary revascularization (RR =0.79, 95% CI, 0.73-0.86, P<0.00001). There was no statistically significant difference between both groups in terms of all-cause mortality (RR =1.01, 95% CI, 0.86-1.20, P=0.86) or CV mortality (RR =0.98, 95% CI, 0.78-1.22, P=0.83). Conclusions PCSK9Is should be strongly considered to improve clinical outcomes in patients at high risk for atherosclerotic CVD.

Clozapine-induced hypersensitivity myocarditis presenting as sudden cardiac death

Hypersensitivity myocarditis is a rare but serious adverse effect of clozapine, a commonly used psychiatric drug. We report the case of sudden cardiac death from clozapine-induced hypersensitivity myocarditis diagnosed at autopsy. A 54-year-old Caucasian male on clozapine therapy for bipolar disorder presented with a sudden onset of shortness of breath. Laboratory studies were significant for elevated N-terminal prohormone of brain natriuretic peptide. During his hospital stay, the patient died of sudden cardiac arrest from ventricular tachycardia. The autopsy revealed hypersensitivity myocarditis, which usually occurs in the first 4 weeks after the initiation of clozapine. A 4-week monitoring protocol, including laboratory assessment of troponin and C-reactive protein, may assist in the early diagnosis of this potentially fatal condition.

Giant Negative T Waves and QT Prolongation in Non-cardiogenic Pulmonary Edema: A Case Report and Review of Literature

Giant negative T-waves have been linked to several cardiac and non-cardiac conditions. However, the presence of giant negative T-waves with QT prolongation in the setting of non-cardiogenic pulmonary edema is a rarely reported, female predominant, and poorly understood electrocardiographic phenomenon. We report a case of a 28-year-old white female who presented with acute diarrhea and was admitted due to acute kidney injury caused by a hemolytic uremic syndrome (HUS). She was managed with multiple blood product transfusions, plasma exchange, and hemodialysis. Subsequently, she developed acute pulmonary edema requiring intubation and urgent hemodialysis. During this acute event, a unique electrocardiographic finding of anterolateral giant negative T-wave and QT prolongation progressively developed and began resolving with the resolution of the pulmonary edema. In addition to our case, 12 cases were reported upon review of the literature with similar electrocardiography (ECG) findings in the setting of non-cardiogenic, non-ischemic pulmonary edema. Giant negative T-waves can be associated with non-cardiac pulmonary edema. Recognition of this rare Wellen’s-like electrocardiographic pattern in a patient without cardiac ischemia is crucial, especially in young females. Basic science and clinicopathological correlation studies are needed to understand the pathophysiology and prognosis behind these ECG findings.

Non-surgical extraction of right atrial mass by AngioVac aspiration device under fluoroscopic and transesophageal echocardiographic guidance

Right-sided cardiac masses are commonly encountered. We present a challenging case of a right atrial thrombus in a patient who had a high surgical risk for open removal. AngioVac aspiration device, under transesophageal echocardiography (TEE) and fluoroscopy guidance, was successfully used to remove the thrombus. The patient tolerated the procedure well and was discharged home. Our case confirms the safety and efficacy of this procedure for treatment of unwanted intracardiac and intravascular masses in patients who are not candidates for conventional therapies of surgery or thrombolytics.