Utility of exercise testing to assess athletes for post COVID-19 myocarditis.

Purpose: This study assessed a functional protocol to identify myocarditis or myocardial involvement in competitive athletes following SARS-CoV2 infection. Methods: We prospectively evaluated competitive athletes (n = 174) for myocarditis or myocardial involvement using the Multidisciplinary Inquiry of Athletes in Miami (MIAMI) protocol, a median of 18.5 (IQR 16-25) days following diagnosis of COVID-19 infection. The protocol included biomarker analysis, ECG, cardiopulmonary stress echocardiography testing with global longitudinal strain (GLS), and targeted cardiac MRI for athletes with abnormal findings. Patients were followed for median of 148 days. Results: We evaluated 52 females and 122 males, with median age 21 (IQR: 19, 22) years. Five (2.9%) had evidence of myocardial involvement, including definite or probable myocarditis (n = 2). Three of the 5 athletes with myocarditis or myocardial involvement had clinically significant abnormalities during stress testing including ventricular ectopy, wall motion abnormalities and/or elevated VE/VCO2, while the other two athletes had resting ECG abnormalities. VO2max, left ventricular ejection fraction and GLS were similar between those with or without myocardial involvement. No adverse events were reported in the 169 athletes cleared to exercise at a median follow-up of 148 (IQR108,211) days. Patients who were initially restricted from exercise had no adverse sequelae and were cleared to resume training between 3 and 12 months post diagnosis. Conclusions: Screening protocols that include exercise testing may enhance the sensitivity of detecting COVID-19 related myocardial involvement following recovery from SARS-CoV2 infection.

Evolution of the Fontan procedure in a single center.

BACKGROUND: Surgical approaches to single ventricle variants include staged, fenestrated, and completed Fontan operations. This study compares outcomes with these modifications of the Fontan operation at a single center. METHODS: Preoperative risk factors and operative results were analyzed by multivariate techniques in 129 patients undergoing modified Fontan operations since March 1988. RESULTS: Overall early and late mortality was 5.4% and 0.8%, respectively. Before 1993, completed Fontan operation using right atrial to pulmonary artery anastomosis without fenestration was performed in the majority of patients (44 of 58; 76%). During this period, 10 of 17 patients at high risk had completed Fontan with three takedowns. In 1994, the staged hemi-Fontan and modified Fontan with a lateral tunnel anastomosis and with or without small fenestration (2.5 to 4 mm) were introduced. The majority of patients at high risk during this period underwent hemi-Fontan followed by fenestrated Fontan with no takedowns. Late atrial dysrhythmias occurred in 6 patients (4.7%), generally with larger fenestrations or right atrial to pulmonary anastomoses. Three patients (2.3%) had a stroke, 2 with large (> or = 4 mm) fenestrations. Of 38 fenestrations, 32 (84%) closed spontaneously by 1 year. No protein-losing enteropathy occurred. Most patients (118 of 121) were in New York Heart Association class I/II 4.5 years postoperatively. By multivariate analysis, only Down's syndrome (p < 0.001) predicted early mortality, whereas both Down's syndrome and a systemic right ventricle decreased late survival (p < 0.006). CONCLUSIONS: Proper selection of patients for modifications of the Fontan procedure resulted in excellent early and late survival with a low incidence of atrial dysrhythmia and stroke. Midterm functional outcomes were excellent.

Valved bovine jugular venous conduits for right ventricular to pulmonary artery reconstruction.

Various valved and nonvalved external right ventricle (RV) to pulmonary artery (PA) conduits have been used to palliate congenital heart anomalies. The ideal conduit has not been found. Reasons for conduit failures include stenosis, thrombosis, calcification of the valve or graft wall, and development of an obstructive peel. We evaluated valved and nonvalved conduits constructed from a glutaraldehyde preserved segment of bovine jugular vein. Bovine jugular conduits (n = 31), 10-13 mm in diameter, were implanted into weight-matched adult mongrel dogs using a standard closed heart technique. Valved conduits (VC, n = 17) were stented at the valve annulus with a Gore-Tex ring, whereas the nonvalved conduits (NC, n = 14) were stented at their midpoint. The proximal PA was tightly banded to 3 mm with a ligature. Cardiac output (CO) and hemodynamic gradients were measured at the time of insertion and 8 months postoperatively. Pulmonary artery angiograms were used to assess bovine jugular conduit regurgitation. All xenografts were evaluated by gross and histologic exam. Two dogs had conduits placed but died for reasons unrelated to the conduit before evaluation. Valved conduit leaflets showed thickening, insignificant thrombus deposition in the base of one or more cusps, and a mild degree of regurgitation as assessed by angiograms. Examination of the NC showed mild conduit thickening and a moderate-to-severe degree of regurgitation as assessed by angiograms. There was a significant difference observed in pulmonary outflow gradients between the VC (11 +/- 2 mm Hg) and NC (17 +/- 2 mm Hg) (p < 0.05), although neither group developed a hemodynamically significant gradient. On gross examination, VC ventricles displayed significantly less evidence of volume and pressure overload compared with the NC ventricle. Valved conduits demonstrated significantly less obstruction and regurgitation. The potential clinical advantages of bovine jugular conduits are their availability, potential durability evidenced by lack of early calcification, and the advantage of not requiring a proximal extension for the RV anastomosis. The presence of a durable and functional xenograft valve in valved conduits may prevent postoperative sequelae in some patients.

Monocusp valve and transannular patch reconstruction of the right ventricular outflow tract: an experimental study.

Repair of congenital right ventricular outflow tract obstruction often requires reconstruction with a transannular patch to alleviate pulmonary stenosis. Post repair pulmonary insufficiency with right ventricular dilatation and volume overload may result and lead to acute or progressive right heart failure. The use of a monocusp valve has been proposed as a means to prevent this problem. Fresh pericardium is well known to fail clinically, leading to pulmonary insufficiency limiting mid- and long-term results. In a chronic dog model (147 +/- 34 days), three valve types were evaluated: 1) polytetrafluoroethylene (PTFE; n = 9), 2) fresh pericardium (PERI; n = 6), and glutaraldehyde fixed pericardium (GLU; n = 6). Hemodynamics, angiography, and echocardiography were performed at implantation and sacrifice. Gross and microscopic pathology were evaluated. No significant differences were found among the three groups with regard to stenosis as evaluated by echocardiography, measured right ventricular wall thickness, and hemodynamic pressure gradients across the valve. By echocardiography, both PTFE (1 of 9) and GLU (0 of 6) showed less regurgitation than PERI (5 of 6) (p < 0.05). This was confirmed by angiography. PTFE showed less neo-intimal hyperplasia, less thrombus formation, and less calcification than GLU or PERI (p = NS). The PTFE monocusp developed no prohibitive gradients, no early pathologic deterioration, and maintained competence compared with the GLU and PERI groups. Although continued investigation of long-term durability and competence of the PTFE monocusp valve is warranted, both PTFE and GLU values seem to demonstrate less regurgitation than the PERI monocusp valve in an adult dog model of right ventricular outflow tract reconstruction.

Donor cardiac troponin T: a marker to predict heart transplant rejection.

BACKGROUND: Noninvasive methodologies have shown poor sensitivity in predicting rejection when compared to serial endomyocardial biopsies. We studied the potential role of donor blood troponin T (Tn-T) as a marker for predicting heart transplant rejection. METHODS: Blood cardiac Tn-T was measured from 16 heart donors. Transplant rejection and cardiac function in the recipients were monitored for 1 year. RESULTS: When data were analyzed based on donor blood Tn-T levels, 6 patients who received hearts from donors with low Tn-T (<0.45+/-0.1 ng/mL) showed no rejection, and patients whose hearts came from donors with higher Tn-T (6.01+/-0.81 ng/mL) developed episodes of high-grade rejection (3A) within 38.5+/-2.1 days after transplantation. Eight patients who received hearts from donors with intermediate levels of Tn-T (3.57+/-0.55 ng/mL) showed mild rejection (grade 1). All recipients had qualitatively normal left ventricular systolic function by serial echocardiography. The mean donor ischemic time was 169+/-47 minutes. CONCLUSIONS: The quality of the donor heart is an important prognostic factor in heart transplantation. It may be possible to identify severely damaged donor organs before transplantation and avoid their use or to develop more aggressive strategies for reducing recurrent acute rejection episodes in high-risk patients.

Effect of obesity on injury risk in high school football players.

Little is known about the relative injury risk of obese adolescent football players. Two high school varsity teams were followed prospectively for injuries after measurement of height, weight, and triceps and subscapular skinfolds during the preseason. Certified athletic trainers who were present at all practices recorded all injuries that required a player to miss at least one practice or game. In all, 98 players were enrolled in the study. Twenty-eight injuries were documented in 24 different players. There were 27 (28%) players with the sum of skinfolds > or = 95th percentile for age; eight of them had nine injuries. The overall prevalence of injuries per player per season was 0.28 for players < or = 95th percentile and 0.33 for players above this percentile (not significant). High body mass (body weight > 90 kg) was associated with a 2.5 times higher relative risk of injury. While this study did not find evidence for an overall higher injury rate in overly fat high school football players, an alarmingly high incidence of obesity was found in this athletic population.