Michael G. McLaughlin

Impact of delay to angioplasty in patients with acute coronary syndromes undergoing invasive management: analysis from the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial.

OBJECTIVES The aim of this study was to determine the impact of delay to angioplasty in patients with acute coronary syndromes (ACS). BACKGROUND There is a paucity of data on the impact of delays to percutaneous coronary intervention (PCI) in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) undergoing an invasive management strategy. METHODS Patients undergoing PCI in the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial were stratified according to timing of PCI after clinical presentation for outcome analysis. RESULTS Percutaneous coronary intervention was performed in 7,749 patients (median age 63 years; 73% male) with NSTE-ACS at a median of 19.5 h after presentation (<8 h [n=2,197], 8 to 24 h [n=2,740], and >24 h [n=2,812]). Delay to PCI>24 h after clinical presentation was significantly associated with increased 30-day mortality, myocardial infarction (MI), and composite ischemia (death, MI, and unplanned revascularization). By multivariable analysis, delay to PCI of >24 h was a significant independent predictor of 30-day and 1-year mortality. The incremental risk of death attributable to PCI delay>24 h was greatest in those patients presenting with high-risk features. CONCLUSIONS In this large-scale study, delaying revascularization with PCI>24 h in patients with NSTE-ACS was an independent predictor of early and late mortality and adverse ischemic outcomes. These findings suggest that urgent angiography and triage to revascularization should be a priority in NSTE-ACS patients.

Paced Left Ventricular QRS Width and ECG Parameters Predict Outcomes After Cardiac Resynchronization Therapy PROSPECT-ECG Substudy

Background— For patients with symptomatic New York Heart Association class III or IV, ejection fraction ⩽35%, and QRS ≥130 ms, cardiac resynchronization therapy (CRT) has become an established treatment option. However, use of these implant criteria fails to result in clinical or echocardiographic improvement in 30% to 45% of CRT patients. Methods and Results— The Predictors of Response to CRT (PROSPECT)-ECG is a substudy of the prospective observational PROSPECT trial. ECGs collected before, during, and after CRT implantation were analyzed. Primary outcomes were improvement in clinical composite score (CCS) and reduction of left ventricular end systolic volume (LVESV) of >15% after 6 months. Age, sex, cause of cardiomyopathy, myocardial infarction location, right ventricular function, mitral regurgitation, preimplantation QRS width, preimplantation PR interval, preimplantation right ventricular–paced QRS width, preimplantation axis categories, LV-paced QRS width, postimplantation axis categories, difference between biventricular (Bi-V) pacing and preimplantation QRS width, and QRS bundle branch morphological features were analyzed univariably in logistic regression models to predict outcomes. All significant predictors (&agr;=0.1), age, and sex were used for multivariable analyses. Cardiomyopathy cause interaction and subanalyses were also performed. In multivariable analyses, only QRS left bundle branch morphological features predicted both CCS (odds ratio [OR]=2.46, P=0.02) and LVESV (OR=2.89, P=0.048) response. The difference between Bi-V and preimplantation QRS width predicted CCS improvement (OR=0.89, P=0.04). LV-paced QRS width predicted LVESV reduction (OR=0.86, P=0.01). Specifically, an LV-paced QRS width of ⩽200 ms was predictive of nonischemic LVESV reduction (OR=5.12, P=0.01). Conclusions— Baseline left bundle branch QRS morphological features, LV-paced QRS width, and the difference between Bi-V and preimplantation QRS width can predict positive outcomes after CRT and may represent a novel intraprocedural method to optimize coronary sinus lead placement. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00253357.

Electrocardiographic Predictors of Arrhythmic Death

Sudden Cardiac Death (SCD) refers to death that occurs within 1 hour of the onset of symptoms. Because the majority of SCD occurs as an unwitnessed out-of-hospital event, data on the exact mechanisms are limited. However, in small series of patients who experienced SCD while wearing an ambulatory monitor1,2 more than 80% of SCD episodes were noted to be due to ventricular tachyarrhythmias; therefore, SCD usually implies arrhythmic death and the terms are often used synonymously. SCD is among the leading causes of death in the developed world, including 350,000–400,000 cases annually in the United States.3,4 Prevention efforts are limited by the unpredictable onset of lethal arrhythmias and the rapid progression to death. Arrhythmia suppression with antiarrhythmic medications has proven ineffective and, in some cases, hazardous.5 Thus, current management strategies have two major components: aggressive treatment of the risk factors and cardiovascular conditions that predispose to SCD (e.g., hypertension, coronary heart disease, and heart failure); and in patients at high risk for arrhythmic death, the increasing use of implantable cardioverter defibrillators (ICDs). Although ICDs have proven to be powerful tools in both the primary6–10 and secondary prevention of SCD,11,12 identifying the patients who should receive an ICD remains a challenge. Current guidelines for ICD implantation include patients at the highest risk of SCD, but this represents only a minority of those who will have an event.13 Paradoxically, many of the patients who are covered by these guidelines will never experience SCD. This paradox is a reflection of the manner in which ICD indications have evolved. ICD indications are derived from randomized trials that,

JOURNAL CLUB: Voice Recognition Dictation: Analysis of Report Volume and Use of the Send-to-Editor Function

OBJECTIVE The purpose of this study was to evaluate use of the send-to-editor function of a radiology voice recognition dictation system and compare study volumes of radiologists who self-edit with those of radiologists who send reports to the editor. Use of voice recognition shortcuts was also evaluated. MATERIALS AND METHODS Voice recognition dictation systems were installed in a six-hospital system, including an 800-bed tertiary care center and five community hospitals, in 2002. This became the only means of radiologist dictation in July 2005. Report volumes, use of the send-to-editor function, and use of shortcuts were tracked from October 2005 through October 2008. A subspecialty private radiology group, ranging from 37 radiologists in July 2005 to 50 radiologists in October 2008, interpreted the imaging studies. Radiologists had no financial incentives to self-edit. RESULTS The percentage of radiologists using the send-to-editor function remained relatively constant at 46%, resulting in 21% of total reports sent to the editor. Radiologists who used the send-to-editor function dictated approximately 41% more reports than those who self-edited. The volume of reports generated by general radiologists reading large volumes of computed radiography cases and sending to the editor was greater than that of radiologists who self-edited (p < 0.05). There was no significant difference between radiologists who self-edited and those who sent to the editor with respect to number of shortcuts used. CONCLUSION Radiologists reading large volumes of computed radiography cases and using the send-to-editor function generated significantly more reports than radiologists who did not, suggesting that the send-to-editor function may be useful for improving productivity among radiologists reading large volumes of computed radiography cases.

Paced Left Ventricular QRS Width and ECG Parameters Predict Outcomes After Cardiac Resynchronization TherapyClinical Perspective: PROSPECT-ECG Substudy

Background— For patients with symptomatic New York Heart Association class III or IV, ejection fraction ⩽35%, and QRS ≥130 ms, cardiac resynchronization therapy (CRT) has become an established treatment option. However, use of these implant criteria fails to result in clinical or echocardiographic improvement in 30% to 45% of CRT patients. Methods and Results— The Predictors of Response to CRT (PROSPECT)-ECG is a substudy of the prospective observational PROSPECT trial. ECGs collected before, during, and after CRT implantation were analyzed. Primary outcomes were improvement in clinical composite score (CCS) and reduction of left ventricular end systolic volume (LVESV) of >15% after 6 months. Age, sex, cause of cardiomyopathy, myocardial infarction location, right ventricular function, mitral regurgitation, preimplantation QRS width, preimplantation PR interval, preimplantation right ventricular–paced QRS width, preimplantation axis categories, LV-paced QRS width, postimplantation axis categories, difference between biventricular (Bi-V) pacing and preimplantation QRS width, and QRS bundle branch morphological features were analyzed univariably in logistic regression models to predict outcomes. All significant predictors (&agr;=0.1), age, and sex were used for multivariable analyses. Cardiomyopathy cause interaction and subanalyses were also performed. In multivariable analyses, only QRS left bundle branch morphological features predicted both CCS (odds ratio [OR]=2.46, P=0.02) and LVESV (OR=2.89, P=0.048) response. The difference between Bi-V and preimplantation QRS width predicted CCS improvement (OR=0.89, P=0.04). LV-paced QRS width predicted LVESV reduction (OR=0.86, P=0.01). Specifically, an LV-paced QRS width of ⩽200 ms was predictive of nonischemic LVESV reduction (OR=5.12, P=0.01). Conclusions— Baseline left bundle branch QRS morphological features, LV-paced QRS width, and the difference between Bi-V and preimplantation QRS width can predict positive outcomes after CRT and may represent a novel intraprocedural method to optimize coronary sinus lead placement. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00253357.

Paced Left Ventricular QRS Width and ECG Parameters Predict Outcomes After Cardiac Resynchronization TherapyClinical Perspective

Background— For patients with symptomatic New York Heart Association class III or IV, ejection fraction ⩽35%, and QRS ≥130 ms, cardiac resynchronization therapy (CRT) has become an established treatment option. However, use of these implant criteria fails to result in clinical or echocardiographic improvement in 30% to 45% of CRT patients. Methods and Results— The Predictors of Response to CRT (PROSPECT)-ECG is a substudy of the prospective observational PROSPECT trial. ECGs collected before, during, and after CRT implantation were analyzed. Primary outcomes were improvement in clinical composite score (CCS) and reduction of left ventricular end systolic volume (LVESV) of >15% after 6 months. Age, sex, cause of cardiomyopathy, myocardial infarction location, right ventricular function, mitral regurgitation, preimplantation QRS width, preimplantation PR interval, preimplantation right ventricular–paced QRS width, preimplantation axis categories, LV-paced QRS width, postimplantation axis categories, difference between biventricular (Bi-V) pacing and preimplantation QRS width, and QRS bundle branch morphological features were analyzed univariably in logistic regression models to predict outcomes. All significant predictors (&agr;=0.1), age, and sex were used for multivariable analyses. Cardiomyopathy cause interaction and subanalyses were also performed. In multivariable analyses, only QRS left bundle branch morphological features predicted both CCS (odds ratio [OR]=2.46, P=0.02) and LVESV (OR=2.89, P=0.048) response. The difference between Bi-V and preimplantation QRS width predicted CCS improvement (OR=0.89, P=0.04). LV-paced QRS width predicted LVESV reduction (OR=0.86, P=0.01). Specifically, an LV-paced QRS width of ⩽200 ms was predictive of nonischemic LVESV reduction (OR=5.12, P=0.01). Conclusions— Baseline left bundle branch QRS morphological features, LV-paced QRS width, and the difference between Bi-V and preimplantation QRS width can predict positive outcomes after CRT and may represent a novel intraprocedural method to optimize coronary sinus lead placement. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00253357.