Combination of contrast with stress echocardiography: A practical guide to methods and interpretation

Contrast echocardiography has an established role for enhancement of the right heart Doppler signals, the detection of intra-cardiac shunts, and most recently for left ventricular cavity opacification (LVO). The use of intravenously administered micro-bubbles to traverse the myocardial microcirculation in order to outline myocardial viability and perfusion has been the source of research studies for a number of years. Despite the enthusiasm of investigators, myocardial contrast echocardiography (MCE) has not attained routine clinical use and LV opacification during stress has been less widely adopted than the data would support. The purpose of this review is to facilitate an understanding of the involved imaging technologies that have made this technique more feasible for clinical practice, and to guide its introduction into the practice of the non-expert user

Genomes of multicellular algal sisters to land plants illuminate signaling network evolution

Zygnematophyceae are the algal sisters of land plants. Here we sequenced four genomes of filamentous Zygnematophyceae, including chromosome-scale assemblies for three strains of Zygnema circumcarinatum. We inferred traits in the ancestor of Zygnematophyceae and land plants that might have ushered in the conquest of land by plants: expanded genes for signaling cascades, environmental response, and multicellular growth. Zygnematophyceae and land plants share all the major enzymes for cell wall synthesis and remodifications, and gene gains shaped this toolkit. Co-expression network analyses uncover gene cohorts that unite environmental signaling with multicellular developmental programs. Our data shed light on a molecular chassis that balances environmental response and growth modulation across more than 600 million years of streptophyte evolution

Clinical Trial Design Principles and Endpoint Definitions for Transcatheter Mitral Valve Repair and Replacement: Part 1: Clinical Trial Design Principles: A Consensus Document From the Mitral Valve Academic Research Consortium.

Mitral regurgitation (MR) is one of the most prevalent valve disorders and has numerous etiologies, including primary (organic) MR, due to underlying degenerative/structural mitral valve (MV) pathology, and secondary (functional) MR, which is principally caused by global or regional left ventricular remodeling and/or severe left atrial dilation. Diagnosis and optimal management of MR requires integration of valve disease and heart failure specialists, MV cardiac surgeons, interventional cardiologists with expertise in structural heart disease, and imaging experts. The introduction of transcatheter MV therapies has highlighted the need for a consensus approach to pragmatic clinical trial design and uniform endpoint definitions to evaluate outcomes in patients with MR. The Mitral Valve Academic Research Consortium is a collaboration between leading academic research organizations and physician-scientists specializing in MV disease from the United States and Europe. Three in-person meetings were held in Virginia and New York during which 44 heart failure, valve, and imaging experts, MV surgeons and interventional cardiologists, clinical trial specialists and statisticians, and representatives from the U.S. Food and Drug Administration considered all aspects of MV pathophysiology, prognosis, and therapies, culminating in a 2-part document describing consensus recommendations for clinical trial design (Part 1) and endpoint definitions (Part 2) to guide evaluation of transcatheter and surgical therapies for MR. The adoption of these recommendations will afford robustness and consistency in the comparative effectiveness evaluation of new devices and approaches to treat MR. These principles may be useful for regulatory assessment of new transcatheter MV devices, as well as for monitoring local and regional outcomes to guide quality improvement initiatives

Impact of Tricuspid Regurgitation on Clinical Outcomes: The COAPT Trial

Background: The presence of tricuspid regurgitation (TR) may affect prognosis in patients with mitral regurgitation (MR). Objectives: This study sought to determine the impact of TR on outcomes in patients with heart failure and severe secondary MR randomized to guideline-directed medical therapy (GDMT) or edge-to-edge repair with the MitraClip in the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation) trial. Methods: A total of 614 patients with symptomatic heart failure with moderate to severe (3+) or severe (4+) secondary MR were randomized to maximally tolerated GDMT plus MitraClip or GDMT alone; 599 had core laboratory evaluable echocardiograms. Patients were divided into 2 groups by baseline TR severity: none/trace/mild TR (≤Mild TR) (n = 501 [83.6%]) and moderate/severe TR (≥Mod TR) (n = 98 [16.4%]). Two-year composite endpoints of death or heart failure hospitalization (HFH) and the individual endpoints were analyzed. Results: Patients with ≥Mod TR were more likely to be New York Heart Association functional class III/IV (p < 0.0001) and have a Society of Thoracic Surgeons score of ≥8 (p < 0.0001), anemia (p = 0.02), chronic kidney disease (p = 0.003), and higher N-terminal pro–B-type natriuretic peptide (p = 0.02) than those with ≤Mild TR. Patients with ≥Mod TR had more severe MR (p = 0.0005) despite smaller left ventricular volumes (p = 0.005) and higher right ventricular systolic pressure (p < 0.0001). At 2 years, the composite rate of death or HFH was higher in patients with ≥Mod TR compared with ≤Mild TR treated with GDMT alone (83.0% vs. 64.3%; hazard ratio: 1.74; 95% confidence interval: 1.24 to 2.45; p = 0.001) but not following MitraClip (48.2% vs. 44.0%; hazard ratio: 1.14; 95% confidence interval: 0.71 to 1.84; p = 0.59). Rates of death or HFH, as well as death and HFH alone, were reduced by MitraClip compared with GDMT, irrespective of baseline TR grade (pinteraction = 0.16, 0.29, and 0.21 respectively). Conclusions: Patients with severe secondary MR who also had ≥Mod TR had worse clinical and echocardiographic characteristics and worse clinical outcomes compared to those with ≤Mild TR. Within the COAPT trial, MitraClip improved outcomes in patients with and without ≥Mod TR severity compared with GDMT alone. (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation [COAPT]; NCT01626079

Predictors of Clinical Response to Transcatheter Reduction of Secondary Mitral Regurgitation: The COAPT Trial

Background: Transcatheter mitral valve repair with the MitraClip results in marked clinical improvement in some but not all patients with secondary mitral regurgitation (MR) and heart failure (HF). Objectives: This study sought to evaluate the clinical predictors of a major response to treatment in the COAPT trial. Methods: Patients with HF and severe MR who were symptomatic on maximally tolerated guideline-directed medical therapy (GDMT) were randomly assigned to MitraClip plus GDMT or GDMT alone. Super-responders were defined as those alive without HF hospitalization and with ≥20-point improvement in the Kansas City Cardiomyopathy Questionnaire overall summary (KCCQ-OS) score at 12 months. Responders were defined as those alive without HF hospitalization and with a 5 to <20-point KCCQ-OS improvement at 12 months. Nonresponders were those who either died, were hospitalized for HF, or had <5-point improvement in KCCQ-OS at 12 months. Results: Among 614 enrolled patients, 41 (6.7%) had missing KCCQ-OS data and could not be classified. At 12 months, there were 79 super-responders (27.2%), 55 responders (19.0%), and 156 nonresponders (53.8%) in the MitraClip arm compared with 29 super-responders (10.2%), 46 responders (16.3%), and 208 nonresponders (73.5%) in the GDMT-alone arm (overall p < 0.0001). Independent baseline predictors of clinical responder status were lower serum creatinine and KCCQ-OS scores and treatment assignment to MitraClip. MR grade and estimated right ventricular systolic pressure at 30 days were improved to a greater degree in super-responders and responders but not in nonresponders. Conclusions: Baseline predictors of clinical super-responders in patients with HF and severe secondary MR in the COAPT trial were lower serum creatinine, KCCQ-OS score and MitraClip treatment. Improved MR severity and reduced right ventricular systolic pressure at 30 days are associated with a long-term favorable clinical response after transcatheter mitral valve repair. (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation [COAPT]; NCT01626079

Pulmonary Hypertension in Transcatheter Mitral Valve Repair for Secondary Mitral Regurgitation: The COAPT Trial

Background: Pulmonary hypertension worsens prognosis in patients with heart failure (HF) and secondary mitral regurgitation (SMR). Objectives: This study sought to determine whether baseline pulmonary hypertension influences outcomes of transcatheter mitral valve repair (TMVr) in patients with HF with SMR. Methods: In the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation) trial, 614 patients with HF with moderate-to-severe or severe SMR were randomized to TMVr with the MitraClip plus guideline-directed medical therapy (GDMT) (n = 302) versus GDMT alone (n = 312). Baseline pulmonary artery systolic pressure (PASP) estimated from echocardiography was categorized as substantially increased (≥50 mm Hg) versus not substantially increased (<50 mm Hg). Results: Among 528 patients, 184 (82 TMVr, 102 GDMT) had PASP of ≥50 mm Hg (mean: 59.1 ± 8.8 mm Hg) and 344 (171 TMVr, 173 GDMT) had PASP of <50 mm Hg (mean: 36.3 ± 8.1 mm Hg). Patients with PASP of ≥50 mm Hg had higher 2-year rates of death or HF hospitalization (HFH) compared to those with PASP of <50 mm Hg (68.8% vs. 49.1%; adjusted hazard ratio: 1.52; 95% confidence interval: 1.17 to 1.97; p = 0.002). Rates of death or HFH were reduced by TMVr versus GDMT alone, irrespective of baseline PASP (pinteraction = 0.45). TMVr reduced PASP from baseline to 30 days to a greater than GDMT alone (adjusted least squares mean: –4.0 vs. –0.9 mm Hg; p = 0.006), a change that was associated with reduced risk of death or HFH between 30 days and 2 years (adjusted hazard ratio: 0.91 per –5 mm Hg PASP; 95% confidence interval: 0.86 to 0.96; p = 0.0009). Conclusions: Elevated PASP is associated with a worse prognosis in patients with HF with severe SMR. TMVr with the MitraClip reduced 30-day PASP and 2-year rates of death or HFH compared with GDMT alone, irrespective of PASP