Evaluation of peak pressure gradients in patients after melody valve implantation: a comparison of cardiac catheterization and doppler echocardiography.

OBJECTIVES: The aim of this study was to determine and quantify the relationship between Doppler echocardiography and cardiac catheterization measurements of the peak right ventricle-pulmonary artery (RV-PA) pressure gradient in patients within 24 hours of Melody valve implantation for treatment of a dysfunctional RV outflow tract (RVOT) conduit or bioprosthetic valve (BPV). BACKGROUND: Patients with a dysfunctional RVOT conduit or BPV are now routinely treated percutaneously with implantation of a Melody valve. However, often the postimplantation catheter measurements of the RV-PA peak gradient do not match the postimplant echo-derived gradients obtained after completion of the procedure. Importantly, these echo gradients are commonly used to monitor patients after implantation over time. METHODS: Medical records of 42 patients with Melody valve implantation were reviewed (men: 25/42; mean age: 22.4 ± 11.2 years; RVOT conduit: 23/42; BPV: 18/42; pulmonic stenosis: 6/42, pulmonic regurgitation: 3/42, both: 33/42). RESULTS: The postimplantation RV-PA peak gradient measured by Doppler echocardiography (within 24 hours of valve implantation) was significantly higher than the measurements acquired by catheterization immediately following implantation (24.2 ± 16.3 mmHg vs. 11.6 ± 8.5 mmHg, P < 0.0001). The relationship showed a moderate-strong correlation (r = 0.65, P < 0.0001) with regression analysis suggesting a linear association in both directions (echo gradient = 1.24 × cath gradient + 9.8, P<0.0001 vs. cath gradient = 0.34 × echo gradient + 3.4, P<0.0001). CONCLUSION: The Doppler echocardiography-derived RV-PA peak gradient within 24 hours of valve implantation is predictably higher than the catheter measured peak gradient immediately following valve implantation. A regression equation was derived to define this important relationship.

Patients with single-ventricle physiology: prognostic implications of stress testing.

This study used a retrospective analysis of adults with single-ventricle physiology to ascertain the predictive power of cardiopulmonary stress-testing parameters in determining patients at increased risk of suffering from adverse clinical outcomes. We found that the specific parameters of percent of maximum predicted heart rate achieved and maximum oxygen consumption were significantly correlated with adverse clinical outcomes in patients with single-ventricle congenital heart disease.

Cardiology electronic consultations: Efficient and safe, but consultant satisfaction is equivocal.

BACKGROUND: Cardiovascular electronic consultation is a new service line in consultative medicine and enables care without in-person office visits. We aimed to evaluate accessibility and time saved as measures of efficiency, determine the safety of cardiology electronic consultations, and assess satisfaction by responding cardiologists. METHODS: Using a mixed-methods approach and a modified time-driven, activity-based, costing framework, we retrospectively analysed cardiology electronic consultations. A random subset of 500 electronic consultations referred between 2013-2017 were reviewed. Accessibility was determined based upon increased number of patients served without the need for an in-person clinic visit. To assess safety, medical records were reviewed for emergency room visits or hospital admission at six months from the initial electronic consultation date. Responding cardiologist satisfaction was assessed by voluntary completion of an online survey. RESULTS: The majority of electronic consultations were related to medication advice, clearance for surgery, evaluation of images, or guidance after abnormal testing. Recommendations included echo (10.8%), stress testing (5.0%), other imaging (4.0%) and other subspecialist referrals (3.8%). Electronic consultations were completed within 0.7±0.5 days of the request, with a time to completion of 5-30 min. Over a six-month follow-up, 13.9% of patients had an in-person visit and 2.2% of patients were hospitalised, but none were directly related to the electronic consultation question. Satisfaction by responding cardiologists was modest. CONCLUSION: In conclusion, within a single-payer system, cardiology electronic consultations represent a convenient and safe alternative for providing consultative cardiovascular care, but further optimization is necessary to minimise electronic consultation fatigue experienced by cardiologists.

Arrhythmogenic Inflammatory Cardiomyopathy: A Review.

Arrhythmogenic inflammatory cardiomyopathy is a recent clinical description of a subgroup of patients with non-ischaemic cardiomyopathy who are referred to electrophysiologists for evaluation and management of ventricular arrhythmias and are found to have evidence of active cardiac inflammation. The identification of these patients is key, since the aetiology of their arrhythmic burden is likely both related to scar-mediated and direct inflammatory mechanisms, which may have different treatment approaches. Evaluation of these patients starts with a full clinical history and physical examination along with echocardiography, as with most patients with cardiomyopathy, however, additional imaging with fluorodeoxyglucose PET-CT and cardiac MRI is crucial. Medical treatment is aimed at targeting traditional neurohumeral mediators to achieve recovery of ejection fraction, in addition to immunosuppressant medication to directly treat inflammation. While medical treatment alone is successful in many patients, some will require further invasive management with electrophysiologic study and radiofrequency catheter ablation.

Mortality Risk Stratification in Fontan Patients Who Underwent Heart Transplantation.

The number of patients who require orthotopic heart transplantation (OHT) for failing Fontan physiology continues to grow; however, the methods and tools to evaluate risk of OHT are limited. This study aimed to identify a set of preoperative variables and characteristics that were associated with a greater risk of postoperative mortality in patients who received OHT for failing Fontan physiology. Thirty-six Fontan patients were identified as having undergone OHT at University of California-Los Angeles Medical Center from 1991 to 2014. Data were collected retrospectively and analyzed. The primary end point was designated as postoperative mortality. After an average follow-up time of 3.5 years, 17 (44%) patients suffered postoperative mortality. Patient characteristics including (1) age <18 years at the time of OHT, (2) Fontan-OHT interval of <10 years, (3) systemic ventricular ejection fraction <20%, (4) moderate-to-severe atrioventricular valve insufficiency, (5) an elevated Model of End-stage Liver Disease, eXcluding INR score, or (6) need for advanced mechanical support before surgery were associated with an increased incidence of postoperative mortality. Using these risk factors, we present a theoretical framework to stratify risk of postoperative death in failing Fontan patients after OHT. In conclusion, a method such as this may aid in the transplantation evaluation and listing process of patients with failing Fontan physiology.