Paced QRS morphology predicts incident left ventricular systolic dysfunction and atrial fibrillation.

BACKGROUND: The prognostic significance of paced QRS complex morphology on surface ECG remains unclear. This study aimed to assess long-term outcomes associated with variations in the paced QRS complex. METHODS: Adult patients who underwent dual-chamber pacemaker implantation with 20% or more ventricular pacing and a 12-lead ECG showing a paced complex were included. The paced QRS was analyzed in leads I and aVL. Long-term clinical and echocardiographic outcomes were compared at 5 years. RESULTS: The study included 844 patients (43.1% female; age 75.0 ±â€¯12.1). Patients with a longer paced QRS (pQRS) duration in lead I had a lower rate of atrial fibrillation (HR 0.80; p = 0.03) and higher rate of systolic dysfunction (HR 1.17; p < 0.001). Total pacing complex (TPC) duration was linked to higher rates of ICD implantation (HR 1.18; p = 0.04) and systolic dysfunction (HR 1.22, p < 0.001). Longer paced intrinsicoid deflection (pID) was associated with less atrial fibrillation (HR 0.75; p = 0.01), more systolic dysfunction (HR 1.17; p < 0.001), ICD implantation (HR 1.23; p = 0.04), and CRT upgrade (HR 1.23; p = 0.03). Exceeding thresholds for TPC, pQRS, and pID of 170, 146, and 112 ms in lead I, respectively, was associated with a substantial increase in systolic dysfunction over 5 years (p < 0.001). CONCLUSIONS: Longer durations of all tested parameters in lead I were associated with increased rates of left ventricular systolic dysfunction. ICD implantation and CRT upgrade were also linked to increased TPC and pID durations. Paradoxically, patients with longer pID and pQRS had less incident atrial fibrillation.

Seasonal Periodicity of Ischemic Heart Disease and Heart Failure.

Seasonal variation for ischemic heart disease and heart failure is known. The interplay of environmental, biological, and physiologic changes is fascinating. This article highlights the seasonal periodicity of ischemic heart disease and heart failure and examines some of the potential reasons for these unique observations.

Circadian Periodicity of Ischemic Heart Disease: A Systematic Review of the Literature.

The authors performed a MEDLINE search to identify reports, published during the last 20 years, focused on circadian variation of acute myocardial infarction (AMI), and prevalence and the ratios between the number of events per hour during the morning and the other hours of the day were calculated. Despite the optimization of interventional and medical therapy of AMI since the first reports of circadian patterns in AMI occurrence, it was found that such a pattern still exists and that AMI happens most frequently in the morning hours.

Association of Pulmonary Hypertension and Monoclonal Gammopathy of Undetermined Significance.

Objective: To determine the prevalence of monoclonal gammopathy of undetermined significance (MGUS) in patients with PH as well as precapillary PH. Methods: Olmsted County residents with PH, diagnosed between 1/1/1995 and 9/30/2017, were identified, and age and sex were matched to a normal control group. The PH group and normal control group were then cross-referenced with the Mayo Clinic MGUS database. Charts were reviewed to verify MGUS and PH. Heart catheterization data were then analyzed in these patients for reference to the gold standard for diagnosis. Results: There were 3419 patients diagnosed with PH by echocardiography between 1995 and 2017 in Olmsted County that met the criteria of our study. When the PH group (N = 3313) was matched to a normal control group (3313), a diagnosis of MGUS was significantly associated with PH 10.2% (OR = l.84 [95% CI 1.5-2.2], p < 0.001), compared with controls 5.8% based on echo diagnosis. Using heart catheterization data (484 patients), a diagnosis of MGUS was associated with PH 13.0% (OR = 3.94 [95% CI 2.28-6.82], p < 0.001). For pulmonary artery hypertension (N = 222), a diagnosis of MGUS was associated with PH at similar 12.2% (OR = 4.50 [95%CI 1.86-10.90], p < 0.001. Conclusions: There is a higher prevalence of MGUS in patients with PH and precapillary PH compared with normal controls. This association cannot be explained fully by other underlying diagnoses associated with PH. Assessing for this in patients with PH of unclear etiology may be reasonable in the workup of patients found to have PH.

Cardiac magnetic resonance in patients with elevated troponin and normal coronary angiography.

BACKGROUND: Invasive angiography in the setting of cardiac troponin elevation may reveal non-obstructive coronary arteries leading to uncertainty in diagnosis. Cardiac MR (CMR) may aid in diagnosis, however, the spectrum of diagnostic findings in the patient presenting with symptoms of cardiac ischaemia, elevated cardiac biomarkers and a negative invasive coronary angiogram is yet to be completely described. METHODS: We queried the Mayo Clinic, Rochester inpatient record from 1 January 2000 to 31 December 2016 to identify patients who: (1) had an elevated troponin T during admission, (2) underwent coronary angiography within 30 days of troponin T elevation which was considered negative for obstructive coronary arterial disease and (3) underwent CMR within 30 days of troponin T elevation. CMR diagnoses were classified as either (1) myocarditis, (2) small area myocardial infarction, (3) stress cardiomyopathy, (4) non-ischaemic cardiomyopathy or (5) normal. RESULTS: Of 215 patients, the spectrum of disease seen on CMR was myocarditis (32%), small area infarction (22%), non-ischaemic cardiomyopathy (20%) and stress cardiomyopathy (9.3%). CONCLUSION: In the largest single-centre study assessing the role of CMR in patients admitted with elevated troponin T with a non-obstructive coronary disease on an angiogram, small area infarction was seen in 22% of patients.

Atrial Fibrillation: Beyond Rate Control.

Atrial fibrillation is the most common cardiac dysrhythmia encountered in the primary care setting. Although a rate control strategy is pursued by physicians for the initial treatment of atrial fibrillation, the efficacy of a rhythm control approach is often undervalued despite offering effective treatment options. There are many pharmacological therapies available to patients, with drug choice often dictated by safety concerns (toxicities and proarrhythmic adverse effects) as well as patient characteristics and comorbidities. This article presents a simplified approach to understanding the rhythm control strategy, including the advantages and disadvantages of various antiarrhythmic drugs and common drug-drug interactions encountered in the primary care setting.

His Bundle (Conduction System) Pacing: A Contemporary Appraisal.

The His bundle (conduction system) is an attractive target for physiologic pacing because it uses the native conduction system. Although the potential benefits of conduction system pacing were recognized in the 1970s, in the past 2 decades, it has grown in interest as a potentially preferred method of ventricular stimulation in appropriate patients. This review provides an appraisal of conduction system pacing, with focus on anatomy, physiology, tools, and techniques as well as an appraisal of current published data and thoughts on future directions.

Clinical, Radiographic, and Microbiologic Features of Infective Endocarditis in Patients With Hypertrophic Cardiomyopathy.

Infective endocarditis (IE) is an infection of the inner lining of the heart with high morbidity and mortality despite medical and surgical advancements in recent decades. Hypertrophic cardiomyopathy (HC) is one of several medical conditions that have been linked to an increased risk of IE, but there is a paucity of data on this association. We therefore sought to define the clinical phenotype of IE in patients with HC at a single tertiary care center. A retrospective cohort of 30 adult patients with HC diagnosed with IE between January 1, 2006 and December 31, 2016 at Mayo Clinic Rochester were identified. Similar rates of aortic (n = 14) and mitral (n = 16) valve involvement by IE were noted (47% vs 53%). This finding persisted even in patients with left-ventricular outflow tract obstruction and systolic anterior motion of the mitral valve. Symptomatic embolic complications occurred in 10 cases (33%). Surgical intervention was performed in 11 cases (37%). One-year mortality was remarkably low at 7%. In conclusion, in the largest single-center cohort of IE complicating HC, there were similar rates of both mitral and aortic valve involvement regardless of the presence of left ventricular outflow tract obstruction, which is contrary to a long-standing tenet regarding the association of HC and IE. Moreover, no "high risk" IE subset was identified based on HC-related parameters.

Non-ST-Segment-Elevation Myocardial Infarction Among Patients With Chronic Kidney Disease: A Propensity Score-Matched Comparison of Percutaneous Coronary Intervention Versus Conservative Management.

BACKGROUND: Chronic kidney disease (CKD) remains an independent predictor of cardiovascular morbidity and mortality. CKD complicates referral for percutaneous coronary intervention (PCI) in non-ST-segment-elevation myocardial infarction (NSTEMI) patients because of the risk for acute kidney injury and the need for dialysis, with American College of Cardiology/American Heart Association guidelines underscoring the limited data on these patients. METHODS AND RESULTS: Using the National Inpatient Sample to analyze hospitalizations in the United States from 2004 to 2014, we sought to assess PCI utilization and in-hospital outcomes in NSTEMI admissions with CKD. NSTEMI admissions were identified by International Classification of Diseases, Ninth Edition, Clinical Modification (ICD-9-CM) code 410.7. CKD admissions were identified by ICD-9-CM code 585. Propensity score-matched cohorts of patients with NSTEMI were matched for age, sex, comorbidities, race, median household income, primary payer status, and hospital characteristics. Of 4 488 795 hospitalizations for NSTEMI, 31% underwent PCI. Overall, 89% of admissions had no CKD. In addition, 32% of NSTEMI admissions with no CKD and 23%, 14%, and 22% with CKD stages 3, 4, and 5 underwent PCI, respectively. Hospitalized NSTEMI patients with CKD stages 4 and 5 had 41% and 20% less likelihood, respectively, of undergoing PCI compared with those with no CKD. Among hospitalized NSTEMI patients with no CKD or CKD stage 3, 4, or 5, PCI-treated groups had 63%, 57%, 39%, and 59% lower likelihood, respectively, of all-cause, in-hospital mortality compared with propensity score-matched medically managed groups. CONCLUSIONS: PCI use decreased among hospitalized NSTEMI patients as CKD severity increased, and all-cause, in-hospital mortality was greater for NSTEMI patients admitted with more severe CKD regardless of treatment strategy.

Dynamic mechanical properties of porcine lacrimal canaliculus.

To better understand the mechanisms of tear drainage, the mechanical properties of porcine canaliculus were measured in compression mode while submerged in isotonic fluid by using a dynamic mechanical analyzer. The storage modulus (E') for the porcine canaliculus is about 3 kPa at 1 Hz and increases to about 5 kPa at 25 Hz. The loss modulus (E'') increases from about 0.8 kPa at 1 Hz to about 4.5 kPa at 25 Hz. The ratio of loss to storage moduli increases with frequency and is about 1 at 25 Hz, which is the relevant frequency during the blink phase. The moduli for 6- to 9-month pigs does not differ significantly from > 2-year-old pigs. The canalicular tissue relaxes at the same timescale as the pressure relaxes in a human canaliculi suggesting that the drainage of tears through the canaliculi is controlled by the mechanical properties of the canaliculi.

Ocular surface sealants and adhesives.

Tissue adhesives, both synthetic and biologic, have a long history of use in ophthalmology. Cyanoacrylate-based glues have traditionally been the most widely used glues for various purposes. They have been specially useful for treating corneal perforations and have had significantly improved long-term outcomes. More recently, fibrin-based glues have gained a major role as a suture substitute for attaching biologic tissues and as surface sealants. The literature supports expanded use of fibrin glue in this fashion. Other new agents, such as polyethyelene glycols, have been underutilized and hold promise, especially as surface protectants. Numerous other glues are being developed and show promise as ocular surface sealants and protective membranes. Advances in knowledge about tissue adhesives are leading to more effective and efficient ophthalmic care.

Racial Differences in the Prevalence and Outcomes of Atrial Fibrillation in Patients Hospitalized With Heart Failure.

Previous research has shown that roughly 15% to 30% of those with heart failure (HF) develop atrial fibrillation (AF). Although studies have shown variations in the incidence of AF in patients with HF, there has been no evidence of mortality differences by race. The purpose of this study was to assess AF prevalence and inhospital mortality in patients with HF among different racial groups in the United States. Using the National Inpatient Sample registry, the largest publicly available all-payer inpatient care database representing >95% of the US inpatient population, we analyzed subjects hospitalized with a primary diagnosis of HF from 2001 to 2011 (n = 11,485,673) using the International Classification of Diseases, Ninth Edition (ICD 9) codes 428.0-0.1, 428.20-0.23, 428.30-0.33, 428.40-0.43, and 428.9; patients with AF were identified using the ICD 9 code 427.31. We assessed prevalence and mortality among racial groups. Using logistic regression, we examined odds of mortality adjusted for demographics and co-morbidity using Elixhauser co-morbidity index. We also examined utilization of procedures by race. Of the 11,485,673 patients hospitalized with HF in our study, 3,939,129 (34%) had AF. Patients with HF and AF had greater inhospital mortality compared with those without AF (4.6% vs 3.3% respectively, p <0.0001). Additionally, black, Hispanic, Asian, and white patients with HF and AF had a 24%, 17%, 13%, and 6% higher mortality, respectively, than if they did not have AF. Among patients with HF and AF, minority racial groups had underutilization of catheter ablation and cardioversion compared with white patients. In conclusion, minority patients with HF and AF had a disproportionately higher risk of inpatient death compared with white patients with HF. We also found a significant underutilization of cardioversion and catheter ablation in minority racial groups compared with white patients.

The relationship between Taekwondo training habits and injury: a survey of a collegiate Taekwondo population.

OBJECTIVE: To correlate training habits of Taekwondo (TKD) athletes to risk for injury. BACKGROUND: TKD is a Korean marital art that has been growing in popularity, with nearly 2 million individuals practicing the sport in the United States. Because of the combative nature of the sport, injuries are an inherent risk. However, data on proper training habits, types of injuries sustained during training, and recommendations for athletes to avoid injury are lacking. Frequently, studies of TKD evaluate athletes' injuries during tournaments, but most do not evaluate athletes in training. HYPOTHESIS: Increased training would potentially create more injuries secondary to increased exposure. METHODS: This is a cross-sectional observational survey of 72 collegiate TKD athletes from the Pacific West Sanctioned Taekwondo Tournaments in the 2008-2009 season. Variables analyzed during training and competitions were training sessions per week, workout habits, belt level, years of experience, and characteristics of injury (location, type, mechanism, situation, treatment, and days missed). RESULTS: TKD training habits of individuals who practiced four or more times per week (odds ratio [OR], 4.5; P=0.005) or sparred for more than 2 hours (OR, 8.7; P=0.003) were associated with significantly increased odds (risk) of sustaining an injury. Those who had more than 3 years of tournament experience were more likely to sustain an injury (OR, 0.198; P=0.020). CONCLUSION: Increased risk for injury with more frequent practice and longer sparring should remind coaches and trainers that monitoring and adjusting the athletes' training schedules and exposure time could decrease the chance of injury. An athlete that has spent more years in tournaments along with high-frequency and long-duration training was associated with greater risk for injuries. Prevention and education about the risk for exposure to injury may may help athletes and trainers promote prevention strategies and adjust an athletes' training and tournament schedules to decrease the risk for injury.