Whether treated with CABG or PCI, heavily calcified lesions tied to higher mortality

Reuters Health - 25/01/2022 - The presence of at least one heavily calcified lesion (HCL) in patients treated for three-vessel and/or left-main-coronary-artery disease is an independent predictor of 10-year mortality, according to a new study.

The findings also show long-term mortality rates were similar in patients with HCLs regardless of whether revascularization was achieved through coronary-artery-bypass grafting (CABG) or percutaneous coronary intervention (PCI). In patients without HCLs, CABG was associated with lower mortality risk.

Not much data is available on very-long-term outcomes of revascularization in patients with HCLs, Dr. Patrick Serruys of the National University of Ireland, in Galway, and colleagues note in JACC: Cardiovascular Interventions

To investigate, they conducted a post-hoc subgroup analysis of the SYNTAX Extended Survival study, encompassing 1,800 patients who received either PCI with paclitaxel-eluting stents or CABG. The subgroup analysis focused on all-cause mortality at 10 years; median follow-up was 11.2 years.

Heavy calcification was defined as radiopacities noted without cardiac motion before contrast injection, generally compromising both sides of the arterial lumen, in vessels 1.5 mm or more in diameter with greater than 50% diameter stenosis.

Of the 1,800 patients, 30% had at least one HCL. These patients were typically older and had higher rates of insulin-treated diabetes, hypertension, previous cerebrovascular disease, peripheral vascular disease, chronic obstructive pulmonary disease, chronic kidney disease and congestive heart failure.

Completeness of revascularization was significantly lower in patients with HCLs, who also had significantly higher 10-year all-cause mortality than did patients without HCLs (P<0.001), regardless of disease type.

There was significant interaction between the mode of revascularization and the presence of HCLs in terms of mortality (P-interaction=0.005). PCI was associated with more deaths than CABG in patients without HCLs (26.0% vs. 18.8%; P=0.003), whereas in patients with HCLs there was no significant difference between the groups (34.0% vs. 39.0%; P=0.264). Multivariable analyses confirmed the findings.

Dr. Serruys and his co-author Dr. Yoshi Onuma, also of the National University of Ireland, cautioned in an email to Reuters Health that their "results should be considered as hypothesis-generating."

Until confirmatory data can be obtained, they added, it's important that the selection of revascularization mode (PCI or CABG) for patients with complex coronary-artery disease be discussed by the multidisciplinary heart team, based on individual risk assessment and possibly taking into account the potential effect of heavy calcification on clinical outcomes.

Drs. Serruys and Onuma described this study as "one of the first trials reporting 10-year comparative outcomes after PCI or CABG in patients with 3-vessel disease/left main disease."

In an accompanying editorial, Dr. Usman Baber of the University of Oklahoma Health Science Center, in Oklahoma City, notes the "somewhat unexpected" finding that even as patients without HCL saw a large and significant reduction in mortality with CABG, "an opposite trend was observed among those with HCL."

A possible explanation for this "muted benefit of CABG is the burden of both extra-cardiac and non-cardiac morbidity among such patients," he adds.

"An intriguing implication of the present work is to consider HCL as a candidate variable in future revascularization risk scores," Dr. Baber says. "In this context HCL appears to function as an integrated imaging-based biomarker that reflects both atherosclerotic and non-atherosclerotic risk."

Dr. Aloke Finn, medical director and chief scientific officer at the CVPath Institute, in Gaithersburg, Maryland, told Reuters Health by email that "perhaps calcification may not be playing a direct role, but rather is a marker for subjects who have many co-morbidities and are more likely to have an increased chance of dying, regardless of the treatment they are offered."

In addition, he cautioned that the data for this analysis come from a trial done more than 10 years ago that "used technologies (especially stents) which would be considered outdated today."

"Nonetheless," concluded Dr. Finn, who was not involved in the study, "the results are intriguing and deserve further investigation."

SOURCE: https://bit.ly/3GP2fQ1 and https://bit.ly/3r1v6ey JACC: Cardiovascular Interventions, online December 29, 2021.

By Scott Baltic



Posted on 25 January 20228 February 2022