Degenerative Mitral Stenosis-Diagnostic Challenges and Future Directions.

Determining the severity of stenosis in degenerative mitral stenosis (DMS) is fraught with challenges. Neither a high trans-mitral gradient nor a small valve area calculation is sufficiently diagnostic for DMS due to variable left atrial and left ventricular compliance in the setting of diastolic dysfunction, and the variable flow seen in patients with chronic kidney disease (i.e., high flow state) and elderly women (low flow state). Three-dimensional measurement of mitral valve area may be underestimated due to shadowing from basal calcium, and mitral valve annulus (MVA) by continuity equation (CEQ) or dimensionless mitral valve index can be erroneous in the presence of significant regurgitation of left-sided valves. The proposed dimensionless mitral stenosis index (DMSI) can be an easy echocardiographic tool to use in daily practice but needs further validation and is limited in the setting of significant regurgitation of left sided valves. Mean trans-mitral gradients > 8 mmHg and pulmonary artery pressure > 50 mmHg are independent predictors of mortality in those with MVA < 1.5 cm 2 derived by CEQ. In patients who have symptoms that are out of proportion to the degree of stenosis reported, exercise stress testing may help determine the physiologic effects of the stenotic valve. A combination of MVA by CEQ or DMSI and mean transmitral gradient at a given left ventricle stroke volume (flow) should be evaluated in larger studies.

Clinical impact of implantable cardioverter-defibrillator in primary prevention of total mortality in non-ischaemic cardiomyopathy: results from a meta-analysis of prospective randomized clinical trials.

Aim: Primary prophylactic implantable cardioverter defibrillators (ICDs) have demonstrated a clear all-cause mortality benefit in patients with ischaemic cardiomyopathy, with less compelling evidence supporting its use in patients with non-ischaemic cardiomyopathy (NICM). We performed a meta-analysis of randomized controlled trials (RCTs) evaluating the role of ICD for reduction in total mortality in NICM patients. Methods and results: An electronic search on PubMed, the Cochrane Library, and EMBASE databases was performed to identify the RCTs evaluating the role of prophylactic ICD placement in NICM patients. Mantel-Haenszel risk ratio (RR) fixed-effects model was used to summarize data across treatment arms. Random-effects model was used if heterogeneity (I2) ≥ 25. Patients with cardiac resynchronization therapy pacemaker (CRT-P) were included in the control group. Six RCTs, with a total of 3128 patients and a mean follow-up period of 48 ± 22 months comparing ICD with medical therapy in NICM were included in this analysis. There was a significant reduction in all-cause mortality in the ICD group compared with the medical therapy group [RR 0.79, 95% confidence interval (95% CI) 0.68-0.92; P = 0.002]. No publication bias was noted. Conclusion: Currently available evidence demonstrates that the use of ICD provides a clear and significant reduction in all-cause mortality among patients with NICM.

Effect of time delay after necropsy on analysis of simian varicella-zoster virus expression in latently infected ganglia of rhesus macaques.

Studies of varicella-zoster virus gene expression during latency require the acquisition of human ganglia at autopsy. Concerns have been raised that the virus might reactivate immediately after death. Because features of varicella-zoster virus latency are similar in primate and human ganglia, we examined virus gene expression in tissues either processed immediately or kept at 4°C for 30 h before necropsy of two monkeys inoculated with simian varicella-zoster virus and euthanized 117 days later. Virus transcription and the detection of open reading frame (ORF) 63 protein in the cytoplasm of neurons were comparable. Thus, a 30-h delay after death did not affect varicella-zoster virus expression in latently infected ganglia.

Simian varicella virus open reading frame 63/70 expression is required for efficient virus replication in culture.

Simian varicella virus (SVV) open reading frame (ORF) 63, duplicated in the virus genome as ORF 70, is homologous to varicella zoster virus ORF 63/70. Transfection of bacterial artificial chromosome clones containing the wild-type SVV genome and mutants with stop codons in ORF 70, in both ORFs 63 and 70 and the repaired virus DNA sequences into Vero cells produced a cytopathic effect (CPE). The onset of CPE was much slower with the double-mutant transfectants (10 days vs. 3 days) and plaques were smaller. While SVV ORF 63 is not required for replication in culture, its expression leads to robust virus replication.

Comparison Between Anatomical and Functional Imaging Modalities for Evaluation of Chest Pain in the Emergency Department.

Evaluation of chest pain in the emergency department (ED) frequently employs a noninvasive strategy, including coronary computed tomography angiography (CCTA), stress echocardiography (SE), or myocardial perfusion imaging (MPI). We sought to report the real-world experience of utilizing CCTA compared with SE and MPI at an urban hospital ED. We conducted a retrospective cohort study of consecutively enrolled patients presenting with chest pain who had normal or nondiagnostic electrocardiogram (ECG), negative initial troponin-T, at least intermediate risk based on modified Diamond-Forrester criteria, and who underwent CCTA, SE, or MPI based on their individual test eligibility criteria. The primary outcome was ED discharge time. Secondary outcomes included test utilization and 30-days rehospitalization rates. The 2,143 patients who were included (mean age was 56 ± 12 years; 55% women) utilization rate (test performed/eligible) was lower for CCTA (n = 354/1,329) and MPI (n = 530/1,435) compared with SE (n = 1,259/1,650), p <0.001. Mean ED discharge times for both CCTA and SE were 12.5 ± 7.4 versus 16 ± 7.3 hours for MPI (p <0.0001). Patients with SE and CCTA were less likely to undergo coronary angiography (29%, 25%, vs 52% for MPI). There was a 1% cardiac-related 30-days rehospitalization rate in the CCTA group versus 1% in SE and 3% in the MPI group (p <0.01). In conclusion, CCTA and SE were associated with faster ED discharge and lower frequency of diagnostic coronary angiography. Notwithstanding its clinical utility, CCTA was underutilized at our large urban ED setting.

Clinical outcomes in patients with atrial fibrillation receiving amiodarone on NOACs vs. warfarin.

PURPOSE: Amiodarone is a potent inhibitor of the CYP450:3A4 and inhibitor of the P-glycoprotein, both of which metabolize new oral anticoagulants (NOACs). Patients who are on NOACs and are concomitantly treated with amiodarone may have a higher risk of major bleeding according to recent retrospective trials. Whether this increased risk outweighs the benefits of NOACs compared to warfarin is unknown. We aimed to compare clinical outcomes between NOACs and warfarin in patients with atrial fibrillation (AF) being treated with amiodarone. METHODS: We performed a systematic review of MEDLINE, Cochrane, and Embase for randomized controlled trials that compared NOACs to warfarin for prophylaxis of ischemic stroke/thromboembolic events (TEs) in patients with AF and reported outcomes on TE, major bleeding, and intracranial bleeding (ICB). Risk ratio (RR) and 95% confidence intervals were measured using the Mantel-Haenszel method. Fixed effects model was used, and if heterogeneity (I2) was > 25%, effects were analyzed using a random model. RESULTS: A total of four studies comparing NOACs to warfarin were included in the analysis. The total number of patients on amiodarone was 6197. Mean follow up was 23 ± 5 months. No statistically significant difference for TE prevention (RR, 0.73; 95% CI 0.50-1.07), major bleeding (RR, 1.02; 95% CI 0.68-1.53), or ICB outcomes (RR, 0.58; 95% CI 0.22-1.51) between patients on NOACs + amiodarone when compared to patients on warfarin + amiodarone. CONCLUSION: Among patients with AF taking amiodarone, there is no increased risk of stroke, major bleeding, or ICB with NOACs compared to warfarin.

The Impact of Gender on Atrial Fibrillation Incidence and Progression to Dementia.

There are a paucity of data regarding the role of gender and atrial fibrillation (AF) on cognitive decline and incidence of dementia. Such data may provide insight into the disproportionate incidence of dementia in women and may help identify high-risk characteristics to target for prevention. We examined patients who underwent coronary angiography at an Intermountain Healthcare Medical Center and enrolled in a prospective cardiovascular database. To be included, patients could not have a previous diagnosis of AF or dementia and had to have 5years of follow-up. Endpoints included incident AF and dementia. Study cohort consisted of 35,608 patients without a previous history of AF or dementia, with 14,377 (40.4%) being woman. Women had lower rates of hypertension, diabetes, coronary artery disease, and prior myocardial infarction, but higher rates of prior stroke. Men had a higher incidence of 5-year and long-term AF. However, women trended toward a higher incidence of 5-year and long-term dementia and stroke compared with men. In all groups of patients with and without AF, prior stroke predicted cognitive decline. In patients without a history of or development of AF, diabetes significantly increased risk of dementia. Women have higher rates of dementia over time than men, driven by higher baseline stroke rates and nontraditional cardiovascular risk factors. The higher dementia rates were in the setting of lower AF rates. However, in both men and women who develop AF, dementia rates are increased and do not show gender-based differences in risk.

The Population-Based Long-Term Impact of Anticoagulant and Antiplatelet Therapies in Low-Risk Patients With Atrial Fibrillation.

Among patients with atrial fibrillation (AF), the risk of stroke risk is a significant concern. CHADS2 and CHA2DS2-VASc ≤2 scoring have been used to stratify patients into categories of risk. Without randomized, prospective data, the need and type of long-term antithrombotic medications for thromboembolism prevention in lower risk AF patients remains controversial. We sought to define the long-term impact of anticoagulant and antiplatelet therapy use in AF patients at low risk of stroke. A total of 56,764 patients diagnosed with AF and a CHADS2 score of 0 or 1, or CHA2DS2-VASc score of 0, 1, or 2 were studied. Antithrombotic therapy was defined as aspirin, clopidogrel (antiplatelet therapy), or warfarin monotherapy (anticoagulation) initiated within 6 months of AF diagnosis. End points included all-cause mortality, cerebrovascular accident, transient ischemic attack (TIA), and major bleed. The average age of the population was 67.0 ± 14.1 years and 56.6% were male. In total, 9,682 received aspirin, 1,802 received clopidogrel, 1,164 received warfarin, and 46,042 did not receive any antithrombotic therapy. Event rates differed between patients with a CHADS2 score of 0 and 1; 18.5% and 37.8% had died, 1.7% and 3.4% had a stroke, 2.2% and 3.2% had a TIA, and 14% and 12.5% had a major bleed, respectively (p <0.0001 for all). The rates of stroke, TIA, and major bleeding increased as antithrombotic therapy intensity increased from no therapy, to aspirin, to clopidogrel, and to warfarin (all p <0.0001). Similar outcomes were observed in low-risk CHA2DS2-VASc scores (0 to 2). In low-risk AF patients with a CHADS2 score of 0 to 1 or CHA2DS2-VASc score of 0 to 2, the use of aspirin, clopidogrel, and warfarin was not associated with lower stroke rates at 5 years compared with no therapy. However, the use of antithrombotic agents was associated with a significant risk of bleed.

Drug-induced torsades de pointes in an underserved urban population. Methadone: is there therapeutic equipoise?

BACKGROUND: Although it has been well established that methadone use can result in prolonged QTc/torsades de pointes (TdP) and has been labeled as one of the main drugs that cause TdP, it is still prescribed indiscriminately, and several cases of methadone-associated TdP have been seen in our community. METHODS: Our objective was to determine the associated factors for prolonged QTc and the development of torsades de pointes (TdP) in our underserved patient population. We found 12,550 ECGs with prolonged QTc between 2002 and 2013. Medical records were reviewed in order to identify precipitating factors for prolonged QTc and to detect incidence of TdP. RESULTS: We identified 2735 patients with prolonged QTc who met the inclusion criteria. Of these, 89 (3%) experienced TdP. There was a greater prevalence of HIV infection in the TdP group (11.2 vs. 3.7%, p < 0.001). Furosemide, hydrochlorothiazide, selective serotonin reuptake inhibitors (SSRIs), amiodarone, ciprofloxacin, methadone, haloperidol, and azithromycin were the drugs most often associated with prolonged QTc (31, 8.2, 7.6, 7.1, 3.9, 3.4 and 3.3%, respectively). However, the agents most commonly associated with TdP were furosemide (39.3%), methadone (27%), SSRIs (19.1%), amiodarone (18%), and dofetilide (9%). The medications with statistical significance in the multivariate analysis for TdP development in descending order were as follows: ranolazine (odds ratios [OR] = 53.61, 95% confidence interval [CI] 5.4-524, p < 0.001), dofetilide (OR = 25, CI 6.47-103.16, p < 0.001), voriconazole (OR = 21.40, CI 3.24-124.25, p < 0.001), verapamil (OR = 10.98, CI 2.62-44.96, p < 0.001), sotalol (OR = 12.72, 1.95-82.81, p = 0.008), methadone (OR = 9.89, CI 4.05-24.15, p < 0.001), and SSRI (OR = 2.26, CI 1.10-5.96, p < 0.001). This multivariate analysis revealed that amiodarone and HIV infection were not implicated in TdP. CONCLUSION: Methadone was by far the leading medication implicated in the development of TdP and an independent predictor in both univariate and multivariate analyses despite the fact that it was not the most common QT-prolonging medication in our population.