‘All-Comers’ Study Shows Survival Benefit of Complete Revascularization in Patients With, Without Diabetes


Incomplete revascularization during PCI increases the risk of long-term mortality for patients with multivessel disease regardless of their diabetes status. In fact, according to a paper published online April 16, 2015, ahead of print in Heart, diabetic patients may stand to gain even more benefit from complete revascularization than their nondiabetic peers. 

Take Home:  ‘All-Comers’ Study Shows Survival Benefit of Complete Revascularization in Patients With, Without Diabetes

Abhiram Prasad, MD, of the Institute of Cardiovascular and Cell Sciences at St. George’s, University of London (London, England), and colleagues looked at 5,350 multivessel disease patients who underwent PCI and were prospectively enrolled in a registry at the Mayo Clinic (Rochester, MN) between January 1997 and June 2011.

Patients were divided into 4 groups based on presence of diabetes and degree of revascularization, with complete being defined as successful PCI to all significant lesions in the segments of interest during index hospitalization. Procedural success was defined as reduction of residual luminal diameter stenosis to no more than 20% without in-hospital death, Q-wave MI, or need for emergency CABG.  Median follow-up duration was 7.9 years. 

Lower Mortality Irrespective of Diabetes Status

Approximately one-quarter of patients (26.6%) had diabetes. Incomplete revascularization was “marginally more frequent,” the paper notes, in those with vs without diabetes (46.9% vs 43.5%; P < .001). 

Numerous baseline characteristics, as expected, differed by diabetes status. Yet even after multivariate adjustment including the Mayo Clinic Risk Score to account for the differences, incomplete revascularization increased the risk of long-term mortality in patients with and without diabetes. Additionally, comorbid diabetes carried a higher risk of death regardless of whether revascularization was complete or incomplete (table 1). Need for repeat revascularization was independently predicted by the presence of diabetes and, within the nondiabetic group only, by incomplete revascularization.

Table 1. Long-term Mortality Risk

Further subgroup analyses showed that the benefit of complete revascularization was evident irrespective of whether PCI occurred in either the BMS era (January 1997-March 2003) or the DES era (April 2003-June 2011) or was performed for either stable disease or ACS.

Crude 5-year mortality rates were higher for patients who had incomplete rather than complete revascularization both in the diabetic group (35.8% vs 21.2%) and the nondiabetic group (22.2% vs 14.1%). Notably, the absolute survival benefit was greater for patients with diabetes.

A ‘Pragmatic Definition’ for Incomplete

According to the authors, the study is “unique in that it provides very long-term follow-up among a large ‘all-comers’ cohort of patients with diabetes who were evaluated to address the impact of [complete revascularization].”

It also addresses practical issues, they say.

One explanation for the “variable frequency and prognostic impact” of incomplete revascularization seen in earlier research on PCI, Dr. Prasad and colleagues suggest, is the lack of a uniform definition of “incomplete.” Typically, definitions have been based on angiographic criteria, they say.

Thus, “there is a need for a practical, simple, intuitive definition of [incomplete revascularization] for clinical studies and practice,” they comment. “The pragmatic definition… used in the present study avoids the need to integrate vessel diameter, a measure that is generally neither recorded in large databases nor routinely measured in practice. Rather, we focused on the proximal coronary segments of the 3 major epicardial arteries as surrogates for large areas of myocardium at jeopardy from significant (> 70% diameter stenosis) atherosclerotic lesions and hence ischemic burden.”

The researchers stress that their “retrospective study cannot establish a causal link” but points to a potentially important role for complete revascularization in patients with diabetes and multivessel disease. “[The optimal strategy] needs to be considered in the context of other variables such as age, LV function, severity of symptoms, myocardial viability, antiplatelet therapy, and coronary anatomy,” they advise.


Source:

Jiménez-Navarro MF, López-Jiménez F, Barsness G, et al. Long-term prognosis of complete percutaneous coronary revascularization in patients with diabetes with multivessel disease. Heart. 2015;Epub ahead of print.

Disclosures:

 

  • Dr. Prasad reports no relevant conflicts of interest.

 

Related Stories:

Comments