Circulation: Clinical Summaries
Original Research Put Into Perspective for the Practicing Clinician
- Overdrive Pacing From Downstream Sites on Multielectrode Catheters to Rapidly Detect Fusion and to Diagnose Macroreentrant Atrial Arrhythmias
- Gestational Age at Birth and Outcomes After Neonatal Cardiac Surgery: An Analysis of the Society of Thoracic Surgeons Congenital Heart Surgery Database
- Effects of Sex on Coronary Microvascular Dysfunction and Cardiac Outcomes
- Early Results of Massachusetts Healthcare Reform on Racial, Ethnic, and Socioeconomic Disparities in Cardiovascular Care
- Patient-Accessible Tool for Shared Decision Making in Cardiovascular Primary Prevention: Balancing Longevity Benefits Against Medication Disutility
- Surgical Revascularization Is Associated With Maximal Survival in Patients With Ischemic Mitral Regurgitation: A 20-Year Experience
- Info & Metrics
Overdrive Pacing From Downstream Sites on Multielectrode Catheters to Rapidly Detect Fusion and to Diagnose Macroreentrant Atrial Arrhythmias
Mapping atrial tachyarrhythmias arising during catheter ablation of atrial fibrillation remains a clinical challenge. Even distinguishing focal from macroreentrant tachycardias may require extensive activation mapping or entrainment from multiple sites with potential tachycardia termination or alteration. We describe how a single pacing maneuver can demonstrate macroreentry by selecting the later (downstream) site for pacing and assessing paced activation at the upstream site. This new method of downstream overdrive pacing allows recognition of constant fusion and thus macroreentry and can indicate if the pacing site is in or near the reentry circuit. This method can be used to rapidly diagnose common atrial tachycardias that arise during catheter ablation of atrial fibrillation and may be useful for the diagnosis of other macroreentrant tachyarrhythmias. See p 2503.
Gestational Age at Birth and Outcomes After Neonatal Cardiac Surgery: An Analysis of the Society of Thoracic Surgeons Congenital Heart Surgery Database
Gestational age at birth is a potentially important modifiable risk factor in neonates with congenital heart disease. Using data from 4784 neonates in the Society of Thoracic Surgeons Congenital Heart Surgery Database, we evaluated the relationship between gestational age and outcomes, focusing on those infants born at early term (ie, 37–38 weeks’ gestation). We found that, when compared with a 39.5-week gestational age reference level, birth at 37 weeks’ gestational age was associated with a higher adjusted odds of in-hospital mortality. Patients born at early term had higher complication rates and prolonged postoperative length of stay. Consistent with previous studies, we confirmed that late-preterm births (ie, 34–36 weeks’ gestation) also had greater mortality and postoperative length of stay. We concluded that birth during the early term period of 37 to 38 weeks’ gestation is associated with worse outcomes after neonatal cardiac surgery. These findings are consistent with associations that have recently been identified between birth at early term and outcomes in neonates without birth defects. These data challenge the commonly held perception that delivery at any time during term gestation is equally safe and appropriate and require that we question the related practice of elective delivery of fetuses with complex congenital heart disease at early term. See p 2511.
Effects of Sex on Coronary Microvascular Dysfunction and Cardiac Outcomes
A large body of literature has demonstrated that men are more likely than women to have both overt and subclinical coronary atherosclerosis. The Women’s Ischemia Syndrome Evaluation study and others have shown that women who present with chest pain frequently exhibit coronary microvascular dysfunction. The extent to which this is an exclusively or predominantly female disorder had been previously poorly studied. Using a cohort of patients referred for clinically indicated stress testing with positron emission tomography for the evaluation of suspected coronary disease who did not exhibit evidence of epicardial coronary stenosis based on the absence of regional perfusion defects, we demonstrate that the prevalence of coronary microvascular dysfunction is similar among both men and women. Indeed, the coronary flow reserve or ratio of stress/rest myocardial blood flow was nearly identical across sexes. Furthermore, the prognostic implications of coronary microvascular dysfunction were similar across sexes: in both cases, impaired coronary flow reserve was associated with a markedly increased risk of major adverse cardiac events. These data suggest that coronary microvascular dysfunction is a common disorder affecting approximately half of members of both sexes referred for stress testing and who may be a target for future therapeutic studies. See p 2518.
Early Results of Massachusetts Healthcare Reform on Racial, Ethnic, and Socioeconomic Disparities in Cardiovascular Care
Healthcare reform in Massachusetts was implemented in April 2006, and in this analysis we examined the early impact of healthcare reform on racial/ethnic, sex, and neighborhood educational level disparities in the receipt of coronary revascularizations (percutaneous coronary angioplasty or coronary artery bypass grafting). Utilizing merged state data sets, among patients hospitalized at nonfederal acute care hospitals, blacks and Hispanics were 30% and 16%, respectively, less likely than whites to receive coronary revascularization after healthcare reform, a finding that is consistent with the prereform period. By contrast, persons living in neighborhoods with higher educational attainment and Asians were more likely to undergo revascularization than patients from relatively lower neighborhood education attainment environments and whites after healthcare reform. Women were 50% less likely to undergo revascularization than men, and privately insured patients were more likely to receive revascularization in both time frames. No differences in 1-year mortality were observed in any of the groups. These data provide early insights into the effect of healthcare reform in Massachusetts on important sociodemographic cardiovascular healthcare disparities, suggesting that reducing insurance barriers to receipt of coronary revascularization has not yet eliminated preexisting differences. See p 2528.
Patient-Accessible Tool for Shared Decision Making in Cardiovascular Primary Prevention: Balancing Longevity Benefits Against Medication Disutility
When we recommend that patients start primary prevention medications, we typically focus on risk as the deciding factor, with no discussion of aversion to taking medication. We rarely estimate the benefit from therapy in tangible terms. In this study, we produced tables of group-mean expectation of lifespan gain from taking a primary prevention therapy such as a statin. This is similar to a risk table, with the exception that younger patients show greater lifespan gain (despite lower short-term risk). We also surveyed 360 members of the general public, asking what level of lifespan gain would make it worth their while taking an imaginary tablet with ideal characteristics. Surprisingly, many demanded an expected lifespan gain larger than that available to any risk stratum of patients. Too little is known about how much patients dislike being on primary prevention medication or why this might be. Future research might explore this more formally. Ultimately, it may help to express to patients the size of the expected survival gain in a manner that can be easily understood. They, too, need a way to express the size of their dislike of being on preventative medication. Both could be expressed on a common scale, in terms of extra lifespan obtained or willing to be given up. If a patient expresses strong dislike of medication, it might trigger further discussion. Ultimately, these steps may help primary prevention becoming more truly personalized medicine. See p 2539.
Surgical Revascularization Is Associated With Maximal Survival in Patients With Ischemic Mitral Regurgitation: A 20-Year Experience
The optimal treatment strategy for ischemic mitral regurgitation remains the subject of active debate. This retrospective, observational analysis of 4989 patients with ischemic mitral regurgitation from a large-volume center compares medical treatment alone, percutaneous coronary intervention, coronary artery bypass grafting, and coronary artery bypass grafting plus mitral valve repair or replacement. Results from this analysis demonstrate that compared with medical management, surgical revascularization with or without treatment of the mitral valve is associated with significantly longer survival for patients with ischemic mitral regurgitation. Coronary artery bypass grafting alone demonstrated the lowest risk of death, and coronary artery bypass grafting with or without mitral valve surgery was associated with better outcomes than either percutaneous coronary intervention or medical therapy. The present study increases the body of evidence for managing ischemic mitral regurgitation by reporting the largest real-world series from the modern era including the full spectrum of treatment strategies. This supplements information from ongoing randomized clinical trials that may lack power to fully detect causal relationships with low-rate events such as mortality and will be an important component of the literature guiding treatment decisions for this disease process. See p 2547.
- © 2014 American Heart Association, Inc.
- Effects of Sex on Coronary Microvascular Dysfunction and Cardiac Outcomes
- Info & Metrics