Optimizing electrophysiology studies to prevent sudden cardiac death after myocardial infarction.

AIMS: This study assessed associations of minimum final extrastimulus coupling interval utilized within electrophysiology study (EPS) after myocardial infarction (MI) and possible site of origin of induced ventricular tachycardia (VT) with long-term occurrence of spontaneous ventricular tachyarrhythmia and long-term survival. METHODS AND RESULTS: This prospective study recruited consecutive patients with left ventricular ejection fraction (LVEF) ≤ 40% who underwent EPS days 3-5 after MI between 2004 and 2017. Positive EPS was defined as sustained monomorphic VT cycle length ≥200 ms for ≥10 s or shorter duration if haemodynamic compromise occurred. Each of the four extrastimuli was shortened by 10 ms at a time, until it failed to capture the ventricle (ventricular refractoriness) or induced ventricular tachyarrhythmia. Outcomes included spontaneous ventricular tachyarrhythmia occurrence and all-cause mortality. Shorter coupling interval length of final extrastimulus that induced VT was associated with higher risk of spontaneous ventricular tachyarrhythmia (P < 0.001). Significantly higher rates of spontaneous ventricular tachyarrhythmia (65.2% vs. 23.2%; P < 0.001) were observed for final coupling interval at EPS <200 ms vs. >200 ms. Right bundle branch block (RBBB) morphology of induced VT, with possible site of origin from the left ventricle, was associated with all-cause mortality [hazard ratio (HR) 3.2, P = 0.044] and a composite of spontaneous ventricular tachyarrhythmia recurrence or mortality (HR 1.8, P = 0.043). CONCLUSION: Ventricular tachycardia induced with shorter coupling intervals was associated with higher risk of spontaneous ventricular tachyarrhythymia on follow-up, indicating that the final extrastimulus coupling interval at EPS early after MI should be determined by ventricular refractoriness. Induced VT with possible origin from left ventricle was associated with increased risk of spontaneous ventricular tachyarrhythmia recurrence or death.

Randomized controlled trial of oxygen saturation targets in very preterm infants: two year outcomes.

OBJECTIVE: To assess whether an oxygen saturation (Spo2) target of 85%-89% compared with 91%-95% reduced the incidence of the composite outcome of death or major disability at 2 years of age in infants born at <28 weeks' gestation. STUDY DESIGN: A total 340 infants were randomized to a lower or higher target from <24 hours of age until 36 weeks' gestational age. Blinding was achieved by targeting a displayed Spo2 of 88%-92% using a saturation monitor offset by ±3% within the range 85%-95%. True saturations were displayed outside this range. Follow-up at 2 years' corrected age was by pediatric examination and formal neurodevelopmental assessment. Major disability was gross motor disability, cognitive or language delay, severe hearing loss, or blindness. RESULTS: The primary outcome was known for 335 infants with 33 using surrogate language information. Targeting a lower compared with a higher Spo2 target range had no significant effect on the rate of death or major disability at 2 years' corrected age (65/167 [38.9%] vs 76/168 [45.2%]; relative risk 1.15, 95% CI 0.90-1.47) or any secondary outcomes. Death occurred in 25 (14.7%) and 27 (15.9%) of those randomized to the lower and higher target, respectively, and blindness in 0% and 0.7%. CONCLUSIONS: Although there was no benefit or harm from targeting a lower compared with a higher saturation in this trial, further information will become available from the prospectively planned meta-analysis of this and 4 other trials comprising a total of nearly 5000 infants.

B-Type Natriuretic Peptide and Long-Term Cardiovascular Mortality in Patients With Coronary Heart Disease.

Background The plasma concentration of B-type natriuretic peptide (BNP) is a strong predictor of adverse cardiovascular events. The aim of this study was to determine whether the association between plasma BNP concentration and cardiovascular mortality is sustained or diminishes with increasing time after BNP is measured. Methods and Results Six thousand seven hundred forty patients with a history of myocardial infarction or unstable angina who participated in the LIPID (Long-Term Intervention with Pravastatin in Ischemic Disease) trial had plasma BNP concentration measured at baseline and after 1 year. Associations with cardiovascular mortality were evaluated in landmark analyses 1 to <5, 5 to <10, and 10 to 16 years after randomization. There were 1640 cardiovascular deaths. The cardiovascular mortality rate increased progressively from 10.2 to 19.1 to 26.3/1000 patient-years from 1 to <5, 5 to <10, and 10 to 16 years after baseline, respectively. The average of baseline and 1-year BNP concentration was more strongly associated with cardiovascular mortality compared with baseline or 1-year BNP only. The hazard ratio (HR) for cardiovascular death associated with each doubling of average BNP concentration was similar during years 1 to <5 (HR, 1.53 [95% CI, 1.44-1.63]), years 5 to <10 (HR, 1.52 [95% CI, 1.44-1.60]), and years 10-16 (HR, 1.43 [95% CI, 1.36-1.50]), P<0.0001 for all. Conclusions BNP concentration remains an independent predictor of cardiovascular mortality more than a decade after it is measured. Because of random variation in plasma concentrations, the average of >1 BNP measurement improves long-term risk prediction.

Persistent psychological distress and mortality in patients with stable coronary artery disease.

BACKGROUND: A single assessment of psychological distress, which includes depression and anxiety, has been associated with increased mortality in patients with coronary heart disease, but the prognostic importance of persistence of distress symptoms is less certain. AIM: To determine whether intermittent and/or persistent psychological distress is associated with long-term cardiovascular (CV) and total mortality in patients with stable coronary artery disease. METHODS: 950 participants in the Long-Term Intervention with Pravastatin in Ischaemic Disease (LIPID) trial completed at least four General Health Questionnaires (GHQ-30) at baseline and after ½, 1, 2 and 4 years. In a landmark analysis from 4 years, Cox proportional hazards models evaluated the risk of CV and total mortality by increasing levels of psychological distress: never distressed, sometimes any severity (GHQ score >5), persistent mild (GHQ score >5 on three or more occasions) and persistent moderate distress (GHQ score >10) on three or more occasions, over a median of 12.1 (IQR 8.6-12.5) years. The models were both unadjusted and adjusted for known baseline risk factors. RESULTS: Persistent moderate or greater psychological stress was reported on three or more assessments by 35 (3.7%) subjects. These patients had a higher risk of both CV death (adjusted HR 3.94, 95% CI 2.05 to 7.56, p<0.001) and all-cause mortality (adjusted HR 2.85, 95% CI 1.74 to 4.66, p<0.001) compared with patients with no distress. In contrast, patients who reported persistent mild distress (n=73, 7.7%) on three or more visits, and those who met criteria for distress on only one or two assessments (n=255, 26.8%), did not have an increased risk of CV or all-cause mortality during follow-up. CONCLUSION: In patients with stable coronary artery disease, persistent psychological distress of at least moderate severity is associated with a substantial increase in CV and all-cause mortality.