• About
  • Masthead
  • License Content
  • Advertise
  • Submit Press Release
  • RSS/Email List
  • Write for us
  • Contact us
2 Minute Medicine
No Result
View All Result

No products in the cart.

SUBSCRIBE
  • Specialties
    • Cardiology
    • Chronic Disease
    • Dermatology
    • Emergency
    • Endocrinology
    • Gastroenterology
    • Imaging and Intervention
    • Infectious Disease
    • Nephrology
    • Neurology
    • Obstetrics
    • Oncology
    • Ophthalmology
    • Pediatrics
    • Preclinical
    • Psychiatry
    • Public Health
    • Pulmonology
    • Rheumatology
    • Surgery
  • The Scan
  • Wellness
  • Classics™
    • 2MM+ Online Access
    • Paperback and Ebook
  • Rewinds
  • Visual
  • Partners
    • License Content
    • Submit Press Release
    • Advertise with Us
  • AccountLog-in/out
    • Subscribe
    • Sign-in
    • My account
2 Minute Medicine
  • Specialties
    • Cardiology
    • Chronic Disease
    • Dermatology
    • Emergency
    • Endocrinology
    • Gastroenterology
    • Imaging and Intervention
    • Infectious Disease
    • Nephrology
    • Neurology
    • Obstetrics
    • Oncology
    • Ophthalmology
    • Pediatrics
    • Preclinical
    • Psychiatry
    • Public Health
    • Pulmonology
    • Rheumatology
    • Surgery
  • The Scan
  • Wellness
  • Classics™
    • 2MM+ Online Access
    • Paperback and Ebook
  • Rewinds
  • Visual
  • Partners
    • License Content
    • Submit Press Release
    • Advertise with Us
  • AccountLog-in/out
    • Subscribe
    • Sign-in
    • My account
SUBSCRIBE
2 Minute Medicine
Subscribe
Home All Specialties Cardiology

QRS morphology and duration associated with cardiac resynchronization outcomes

bys25qthea
August 14, 2013
in Cardiology, Chronic Disease, Surgery
Reading Time: 3 mins read
0
Share on FacebookShare on Twitter

Image: PD 

1. Heart failure patients with left bundle branch block (LBBB) and QRS durations of 150 ms or greater had better outcomes after cardiac resynchronization defibrillator placement. Patients with both LBBB and QRS > 150ms had 3-year mortality of 20.9%, while patients with neither had 3-year mortality of 32.3%. 

2. Heart failure patients receiving cardiac resynchronization defibrillators without LBBB and with a QRS duration of 120-149 ms were found to have the highest rate of adverse outcomes. 

Evidence Rating Level: 2 (Good)            

Study Rundown: Previous studies have shown cardiac resynchronization therapy (CRT) to be an effective therapy for heart failure patients.  However, not all patients receiving this therapy have beneficial outcomes.  This study sought to characterize patients who would be good candidates for CRT based upon QRS morphology and duration.  Ultimately, the authors showed that heart failure patients with left bundle branch block (LBBB) and QRS durations of 150 ms or greater were most likely to have good outcomes with cardiac resynchronization defibrillator placement (i.e. lower readmission rates and mortality).  They also found that patients with QRS durations between 120-149 ms were most likely to have adverse outcomes.  Given the known association of LBBB and widened QRS intervals with heart failure mortality, likely in part due to cardiac dyssynchrony, the results appear support this biological relationship. A major strength of this study, in addition to its large sample size, is that it is the first to include both patients who were admitted for CRT and those who were admitted for other reasons.  An inherent limitation of the study, given its retrospective, cohort design, is that there was no control group. While the study provides evidence supporting the use of QRS morphology and QRS interval duration when considering CRT in heart failure patients, future research should validate and replicate the findings of this study.

Click to read the study, published today in JAMA

Relevant Reading: Cardiac resynchronization therapy for patients with left ventricular systolic dysfunction: a systematic review

RELATED REPORTS

The MADIT-CRT trial: Cardiac resynchronization therapy in heart failure [Classics Series]

Cardiac Resynchronization Therapy may be more beneficial in women

Resynchronization improves survival in mild heart failure, heart block [MADIT-CRT trial]

In-Depth [retrospective cohort study]: This study included 24,169 patients from the National Cardiovascular Data Registry’s Implantable Cardioverter-defibrillator Registry who were Medicare fee-for-service beneficiaries receiving cardiac resynchronization therapy-defibrillators.  Data on patients was collected for 3 years and data on all-cause mortality, all-cause readmission, cardiovascular readmission, heart failure readmission, and complications were used.  At one year, patients with LBBB and QRS duration of 150 ms or greater had better rates of all outcomes; the mortality rate was 5.6% and the readmission rate was 38.6%.  The adjusted risk of 3 year mortality was also lowest in this population with LBBB and QRS duration of 150ms or greater at 20.9%.  The second lowest 3 year mortality rate was in patients with LBBB and QRS durations between 120-149 ms (26.5%, HR 1.30 99% CI 1.18-1.42).  Patients with no LBBB but QRS duration of 150ms or greater had 3-year mortality of 30.7. The highest 3 year mortality rate was among patients with no LBBB and QRS durations between 120-149 ms (32.3%, HR 1.52, 99%CI 1.38-1.67).

By Jeffrey Cohen and Rif Rahman

More from this author: Link of low vitamin D with coronary heart disease varies by race, Most physicians point to others to control healthcare costs 

© 2013 2minutemedicine.com. All rights reserved. No works may be reproduced without expressed written consent from 2minutemedicine.com. Disclaimer: We present factual information directly from peer reviewed medical journals. No post should be construed as medical advice and is not intended as such by the authors, editors, staff or by 2minutemedicine.com. PLEASE SEE A HEALTHCARE PROVIDER IN YOUR AREA IF YOU SEEK MEDICAL ADVICE OF ANY SORT. 

Tags: cardiac resynchronization defibrillatorleft bundle branch blockqrs
Previous Post

Early surgical intervention for mitral regurgitation associated with greater long-term survival

Next Post

Mixed results regarding finasteride for prostate cancer prevention

RelatedReports

Adverse pregnancy outcomes associated with thrombophilias [Classics Series]
General Medicine Classics

The MADIT-CRT trial: Cardiac resynchronization therapy in heart failure [Classics Series]

January 22, 2016
Cardiac Resynchronization Therapy may be more beneficial in women
Cardiology

Cardiac Resynchronization Therapy may be more beneficial in women

June 24, 2014
Spironolactone not beneficial in heart failure with preserved ejection fraction [TOPCAT trial]
Cardiology

Resynchronization improves survival in mild heart failure, heart block [MADIT-CRT trial]

April 30, 2014
Next Post
Androgen deprivation in prostate cancer: intermittent may compromise survival

Mixed results regarding finasteride for prostate cancer prevention

Study lends support for interferon-free treatment of hepatitis C

Study lends support for interferon-free treatment of hepatitis C

MRI-guided ultrasound thalamotomy may reduce essential tremor

MRI-guided ultrasound thalamotomy may reduce essential tremor

License Our Award-Winning Physician-Written Medical News and Visual Abstracts

2 Minute Medicine is the leading authoritative medical news licensing service, and the only with reports written by practicing doctors.

LICENSE CONTENT

2MM+ Premium Access

No ads & unlimited access to all current reports, over 9000 searchable archived reports, visual abstracts, Weekly Rewinds, and the online edition of The Classics Series™ textbook.

Subscription Options
2 Minute Medicine

2 Minute Medicine® is an award winning, physician-run, expert medical media company. Our content is curated, written and edited by practicing health professionals who have clinical and scientific expertise in their field of reporting. Our editorial management team is comprised of highly-trained MD physicians. Join numerous brands, companies, and hospitals who trust our licensed content.

Recent Reports

  • #VisualAbstract: Torsemide does not provide additional decrease in mortality compared to furosemide among patients hospitalized for heart failure
  • Community-based adult vision screening program increases access to eye care
  • Aspirin thromboprophylaxis noninferior to low-molecular-weight heparin in patients with fractures
License Content
Terms of Use | Disclaimer
Cookie Policy
Privacy Statement (EU)
Disclaimer

© 2021 2 Minute Medicine, Inc. - Physician-written medical news.

  • Specialties
    • Cardiology
    • Chronic Disease
    • Dermatology
    • Emergency
    • Endocrinology
    • Gastroenterology
    • Imaging and Intervention
    • Infectious Disease
    • Nephrology
    • Neurology
    • Obstetrics
    • Oncology
    • Ophthalmology
    • Pediatrics
    • Preclinical
    • Psychiatry
    • Public Health
    • Pulmonology
    • Rheumatology
    • Surgery
  • The Scan
  • Wellness
  • Classics™
    • 2MM+ Online Access
    • Paperback and Ebook
  • Rewinds
  • Visual
  • Partners
    • License Content
    • Submit Press Release
    • Advertise with Us
  • Account
    • Subscribe
    • Sign-in
    • My account

© 2021 2 Minute Medicine, Inc. - Physician-written medical news.

Want more physician-written
medical news?

Join over 10 million yearly readers and numerous companies. For healthcare professionals
and the public.

Subscribe for free today!

Subscription options