Meta-Analysis
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Nov 26, 2020; 12(11): 559-570
Published online Nov 26, 2020. doi: 10.4330/wjc.v12.i11.559
Medical therapy vs early revascularization in diabetics with chronic total occlusions: A meta-analysis and systematic review
Muhammad Shayan Khan, Farhad Sami, Hemindermeet Singh, Waqas Ullah, Ma'en Al-Dabbas, Khalid Hamid Changal, Tanveer Mir, Zain Ali, Ameer Kabour
Muhammad Shayan Khan, Internal Medicine, Mercy Saint Vincent Medical Centre, Toledo, OH 43608, United States
Farhad Sami, Internal Medicine, University of Kansas School of Medicine, Kansas City, Kansas, 66202, United States
Hemindermeet Singh, Ma'en Al-Dabbas, Ameer Kabour, Department of Cardiovascular Fellowship, Mercy St Vincent Medical Center and Hospital, Toledo, OH 43608, United States
Waqas Ullah, Internal Medicine, Abington Jefferson Health, Abington, Abington Township, Montgomery County, PA 19001, United States
Khalid Hamid Changal, Department of Cardiovascular Medicine, University of Toledo, Toledo, OH 43606, United States
Tanveer Mir, Internal Medicine, Detroit Medical Center, Detroit, MI 48201, United States
Zain Ali, Internal Medicine, Abington Jefferson Health, Philadelphia, PA 19001, United States
Author contributions: Khan MS contributed to concept and design of the manuscript including the acquisition, analysis and interpretation of data as primary and corresponding author; Sami FA and Changal KH had substantial contributions to the conception or design of the work, provided the majority of images; Singh H, Ullah W, Al-Dabbas M contributed to the analysis of cases including drafting the work for important intellectual content; Mir T, Kabour A and Ali Z had substantial contributions to the conception or design of the work, provided the majority of images and drafted the work critically including the final version and agreed to be accountable for all aspects of the work. All authors revised the work critically including the final version and agreed to be accountable for all aspects of the work.
Conflict-of-interest statement: Authors report no conflict of interest.
PRISMA 2009 Checklist statement: The Authors have read the PRISMA checklist and the manuscript was prepared and revised according to the 2009 PRISMA check list.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Muhammad Shayan Khan, MBBS, MD, Doctor, Internal Medicine, Mercy Saint Vincent Medical Centre, 2213 Cherry Street, Toledo, OH 43608, United States. muhammadshayankhan1@gmail.com
Received: July 6, 2020
Peer-review started: July 6, 2020
First decision: September 17, 2020
Revised: September 30, 2020
Accepted: October 29, 2020
Article in press: October 29, 2020
Published online: November 26, 2020
Processing time: 142 Days and 13.1 Hours
Abstract
BACKGROUND

Management of chronic total occlusions (CTO) in diabetics is challenging, with a recent trend towards early revascularization [ER: Percutaneous coronary intervention (PCI) and bypass grafting] instead of optimal medical therapy (OMT). We hypothesize that ER improves morbidity and mortality outcomes in diabetic patients with CTOs as compared to OMT. 

AIM

To determine the long term clinical outcomes and to compare morbidity and mortality between OMT and ER in diabetic patients with CTOs.

METHODS

Potentially relevant published clinical trials were identified in Medline, Embase, chemical abstracts and Biosis (from start of the databases till date) and pooled hazard ratios (HR) computed using a random effects model, with significant P value < 0.05. Primary outcome of interest was all-cause death. Secondary outcomes included cardiac death, prompt revascularization (ER) or repeat myocardial infarction (MI). Due to scarcity of data, both Randomized control trials and observational studies were included. 4 eligible articles, containing 2248 patients were identified (1252 in OMT and 1196 in ER). Mean follow-up was 45-60 mo.

RESULTS

OMT was associated with a higher all-cause mortality [HR: 1.70, 95% confidence interval (CI): 0.80-3.26, P = 0.11] and cardiac mortality (HR: 1.68, 95%CI: 0.96-2.96, P = 0.07). Results were close to significance. The risk of repeat MI was almost the same in both groups (HR: 0.97, 95%CI: 0.61-1.54, P = 0.90). Similarly, patients assigned to OMT had a higher risk of repeat revascularization (HR: 1.62, 95%CI: 1.36-1.94, P < 0.00001). Sub-group analysis of OMT vs PCI demonstrated higher all-cause (HR: 1.98, 95%CI: 1.36-2.87, P = 0.0003) and cardiac mortality (HR: 1.87, 95%CI: 0.96-3.62, P = 0.06) in the OMT group. The risk of repeat MI was low in the OMT group vs PCI (HR: 0.53, 95%CI: 0.31-0.91, P = 0.02). Data on repeat revascularization revealed no difference between the two (HR: 1.00, 95%CI: 0.52-1.93, P = 1.00).

CONCLUSION

In diabetic patients with CTO, there was a trend for improved outcomes with ER regarding all-cause and cardiac death as compared to OMT. These findings were reinforced with statistical significance on subgroup analysis of OMT vs PCI.

Keywords: Coronary angiography; Diabetes mellitus; Percutaneous coronary Intervention; Coronary bypass grafts; Chronic total occlusions; Mortality

Core Tip: There is a well-known association with worse outcomes from chronic total occlusions in diabetics. These lesions have been traditionally treated with optimal medical therapy (OMT) with the standard of care for revascularization being coronary artery bypass grafting with little evidence of superiority over OMT. Our results reveal for the first time a trend towards superiority of the prompt revascularization group to OMT in terms of all cause and cardiac death in diabetics with chronic total occlusions. These findings were reinforced on subgroup analysis. However, patients undergoing percutaneous coronary intervention had a higher risk of repeat fatal and non-fatal myocardial infarction as compared to OMT. The risk for repeat revascularization was similar in both groups.