Appropriate use of multimodality stress testing for chest pain in new patient referrals to cardiologists.

OBJECTIVE: In response to the growing use of imaging-based cardiac stress tests in the evaluation of stable ischemic heart disease, professional societies have developed appropriate use criteria (AUC). AUC will soon be linked to reimbursement of advanced diagnostic imaging for Medicare beneficiaries via Clinical Decision Support Mechanisms (CDSMs). We sought to characterize the frequency and type of stress test utilization for chest pain referrals evaluated by cardiologists and determine appropriateness. METHODS: We conducted a retrospective review of new patient referrals seen by general cardiologists at an academic medical center between 2016 and 2017 for a diagnosis of chest pain or angina. Type of stress test ordered, if any, and its appropriateness (Appropriate, May be appropriate, and Rarely appropriate) were ascertained based on the 2013 multimodality AUC guideline document. RESULTS: There were 535 total outpatients. After applying exclusion criteria, there were 349 patients in the sample; the average age was 52 ± 15 years and 53% were female. Most chest pain was nonanginal (65%). Pretest probability of CAD was most commonly intermediate (54%). A total of 183 patients (52%) were referred for stress testing. The majority of stress tests were considered appropriate (82%) by AUC. CONCLUSION: Most patients referred to cardiologists for evaluation of chest pain or angina had nonanginal chest pain and an intermediate pretest probability of CAD. Stress testing was ordered in about half of these patients and the majority were considered appropriate by AUC. These findings suggest that indiscriminate use of CDSMs may not be warranted.

Evaluation of failed prosthetic valves in the valve-in-valve era: Potential for utilizing positron emission tomography/computed tomography to recognize infective endocarditis.

Bioprosthetic valve dysfunction was treated in the past with redo open heart surgery. The need to identify occult leaflet infection was not an important requirement as all valve tissue was removed during surgery. With the dramatic growth in transcatheter aortic valve replacement (TAVR) valve-in-valve (ViV) therapy, identification of occult infection is of major significance. TAVR should be rarely performed in infected prosthetic valves and the optimal approach should include open heart surgery and removal of infected tissue. With surgical implants, it can be challenging to distinguish infection from degeneration. The use of advanced imaging modalities, including 18F-fluorodeoxyglucose positron emission tomography/computed tomography, in the diagnosis of occult infection is emerging. We report the use of this imaging modality to identify or exclude endocarditis in patients with prosthetic valves who were candidates for ViV therapy.

Management of Refractory Ventricular Fibrillation (Prehospital and Emergency Department).

Ventricular fibrillation is a life-threatening cardiac arrhythmia that leads to a loss of cardiac function and sudden cardiac death. In this review, we summarize therapeutic interventions and guidelines for providers managing patients with out-of-hospital cardiac arrest and refractory ventricular fibrillation in prehospital and emergency settings. Additionally, we review invasive management, including urgent coronary angiography, extracorporeal membrane oxygenation, and novel strategies for managing refractory ventricular fibrillation arrest. Although the majority of patients with refractory VF do not respond to conventional therapy, recent trials of novel strategies demonstrate encouraging results.

Concomitant Use of Antiplatelets and Anticoagulants in Patients with Coronary Heart Disease and Atrial Fibrillation: What Do Recent Clinical Trials Teach Us?

PURPOSE OF REVIEW: Coronary heart disease (CHD) and atrial fibrillation (AF) are among the most common cardiovascular diseases. A significant proportion of patients have both CHD and AF and are at increased risk for thrombotic complications. Current therapy for CHD and AF includes antiplatelet and anticoagulant medications, respectively. Patients with concurrent CHD and AF may be prescribed dual antiplatelet therapy (DAPT) in addition to anticoagulation, which increases their bleeding risk. Controversy remains on how to balance risks and benefits in patients with CHD and AF in which multiple antithrombotic therapies may be indicated. RECENT FINDINGS: We review clinical trials and current guidelines for antiplatelet and anticoagulant therapy in CHD and AF. Aspirin and P2Y12 inhibitors are the mainstay of antiplatelet therapy. Vitamin K antagonists (VKAs) are the most commonly used anticoagulant, although the use of non-VKA oral anticoagulants (NOACs) in patients with AF is increasing. Recent studies provide guidance on how to address antithrombotic therapies in patients with concomitant CHD and AF. To date, we have evidence that in patients with AF who undergo percutaneous coronary intervention (PCI), clopidogrel with VKA may be used safely without aspirin. Also, low-dose rivaroxaban in combination with either clopidogrel only or DAPT is as effective as the traditional regimen of triple therapy with VKA and DAPT with lower bleeding risk. Dabigatran with a P2Y12 inhibitor was also found to be safe with less bleeding compared to triple therapy with VKA and DAPT. Use of a single antiplatelet agent with anticoagulation has become a viable choice in patients with CHD and AF, but more clinical trial data is needed to confirm therapy and duration regimens.

Factors associated with performing urgent coronary angiography in out-of-hospital cardiac arrest patients.

OBJECTIVES: Factors associated with performing urgent coronary angiography (UCA) in patients with out-of-hospital cardiac arrest (OHCA) were identified. BACKGROUND: Current guidelines for resuscitated OHCA patients recommend UCA if there is ST-elevation on post-arrest electrocardiogram or high suspicion of acute myocardial infarction. Some have advocated for UCA in all OHCA regardless of suspected etiology. The reasons for variations in performing UCA are not well understood. METHODS: A retrospective analysis of subjects presenting with resuscitated OHCA to a single academic medical center from 12/15/2007 to 8/31/2014 was conducted. Demographic and clinical characteristics of patients undergoing UCA, defined as angiography within 6 hr of presentation, were compared with those not undergoing UCA. Logistic regression was used to determine predictors of UCA. RESULTS: A total of 323 resuscitated OHCA patients (mean age, 64 years; women, 35%) were included in the analysis; 107 (33.1%) underwent coronary angiography during their hospitalization and 66 (20.4%) underwent UCA. Multivariable adjusted factors associated with UCA were ST-elevation [odds ratio (OR) 14.66, 95% confidence interval (CI) 6.28-34.24, P < 0.001], initial shockable rhythm (OR 3.69, 95% CI 1.52-8.97, P = 0.004), and history of coronary artery disease (CAD) (OR 3.37, 95% CI 1.43-7.95, P = 0.005). Higher age (OR 0.71 per decade, 95% CI 0.55-0.92, P = 0.01) and obvious non-cardiac cause of arrest (OR 0.08, 95% CI 0.02-0.38, P = 0.001) were negatively associated with UCA. CONCLUSIONS: In resuscitated out-of-hospital cardiac arrest patients, ST-elevation, shockable rhythm, and history of CAD were associated with performing urgent coronary angiography; older patients and those with obvious non-cardiac causes of arrest were negatively associated.

Prospective Comparison of Diagnostic Accuracy Between Point-of-Care and Conventional Ultrasound in a General Diagnostic Department: Implications for Resource-Limited Settings.

OBJECTIVES: To compare the diagnostic accuracy of hand-held point-of-care (POC) versus conventional sonography in a general diagnostic setting with the intention to inform medical providers or clinicians on the rational use of POC ultrasound in resource limited settings. METHODS: Over 3 months in 2010, 47 patients were prospectively enrolled at a single academic center to obtain 54 clinical conventional ultrasound examinations and 54 study-only POC ultrasound examinations. Indications were 48% abdominal, 26% retroperitoneal, and 24% obstetrical. Nine blinded readers (sonographers, residents, and attending radiologists) sequentially assigned diagnoses to POC and then conventional studies, yielding 476 interpreted study pairs. Diagnostic accuracy was obtained by comparing POC and conventional diagnoses to a reference diagnosis established by the unblinded, senior author. Analysis was stratified by study type, body mass index (BMI), diagnostic confidence, and image quality. RESULTS: The mean diagnostic accuracy of conventional sonography was 84% compared with 74% for POC (P < .001). This difference was constant regardless of reader, exam type, or BMI. The sensitivity and specificity to detect abnormalities with conventional was 85 and 83%, compared with 75 and 68% for POC. The POC sonography demonstrated greater variability in image quality and diagnostic confidence, and this accounted for lower diagnostic accuracy. When image quality and diagnostic confidence were similar between POC and conventional examinations, there was no difference in accuracy. CONCLUSIONS: Point-of-care was nearly as accurate as conventional sonography for basic, focused examinations. Observed differences in accuracy were attributed to greater variation in POC image quality.

Therapeutic hypothermia-induced electrocardiographic changes and relations to in-hospital mortality.

BACKGROUND: Therapeutic hypothermia improves survival for selected patients who remain comatose after cardiac arrest. Hypothermia triggers changes in electrocardiographic (ECG) parameters; however, the association of these changes to in-hospital mortality remains unclear. HYPOTHESIS: QT interval changes induced by therapeutic hypothermia are not associated with in-hospital mortality. METHODS: We retrospectively compared precooling ECG parameters to ECG parameters during hypothermia on all consecutive patients with available information who received hypothermia at our academic medical center between December 2006 and July 2012 (N = 101; 24% women). Paired 2-sample t test was used to compare precooling vs cooling ECG parameters. In-hospital mortality related to ECG parameter changes was compared using the Pearson χ(2) test. RESULTS: Therapeutic hypothermia resulted in increases in PR and QTc intervals and decreases in heart rate and QRS intervals (P for all <0.02). During hospitalization, 45 of the 101 patients died. Survivors vs nonsurvivors did not differ in heart rate change (P = 0.74), PR change (P = 0.57), QRS change (P = 0.09), or QTc change (P = 0.67). Comparing patients who had reduced QTc intervals with hypothermia to those who had prolonged QTc with hypothermia, 14 out of 30 died in the former group, whereas 31 out of 71 died in the latter group (46.7% vs 43.7%, odds ratio [OR]: 1.13, 95% CI: 0.48-2.66). Patients presenting with right bundle branch block (RBBB) had a higher risk of in-hospital death compared to those without RBBB (72.2% vs 38.6%, OR: 4.14, 95% CI: 1.35-12.73). CONCLUSIONS: Therapeutic hypothermia prolonged QTc interval with no association to in-hospital mortality. Presence of RBBB on initial presentation was related to increased mortality.