PPCI Not Enough to Stave Off Acute MI Mortality, European Data Imply

MUNICH, Germany—Wider access to primary percutaneous coronary intervention (PPCI) does not, at least on a population level, necessarily bolster survival after acute myocardial infraction, according to newly analyzed European data.

Ali Malik (King’s College London, England), presented the findings at last week’s inaugural European Association of Percutaneous Cardiovascular Interventions (EAPCI) Summit.

Over the years, “we’ve seen a large rise in PCI provision, yet disparities and differences in death rates exist in terms of acute myocardial infarction death rates across all of Europe,” Malik said in the moderated ePoster session. “So, we wanted to see why this may be and assess the trends and elucidate the causes behind this.”

For the cross-sectional study of 21 countries, Malik et al turned to the European Society of Cardiology (ESC) Atlas of Cardiology and ESC Atlas in Interventional Cardiology combined with data from the Worth Health Organization, the Institute for Health Metrics and Evaluation, and Eurostat.

Higher gross domestic product (GDP) per capita was tied to lower acute MI mortality, with a population correlation efficient (ƿ) of -0.54 (P = 0.004). Higher prevalence of cardiovascular disease, on the other hand, was associated with higher acute MI mortality (ƿ = +0.45; P = 0.02). Yet mortality did not significantly correlate with operator PPCI volume (P = 0.23).

After adjusting for CVD prevalence and GDP, the researchers looked at the association between the rates of PPCI per 1 million people and age-standardized acute MI mortality—counterintuitively, as the PPCI rate rose, so too did acute MI mortality (ƿ = +0.68; P < 0.001).

The association between PPCI and mortality was “attenuated in middle- and high-income GDP tertiles, but still the result was . . . significant,” said Malik. The correlation was “very strong” within the low-income tertile.

“Higher PPCI availability does not independently translate into lower acute MI mortality after recounting for economic status and disease burden, and other factors may also play a significant role,” Malik concluded. This finding “highlights that perhaps just expanding the ability of countries to provide PPCI, on its own, may have diminishing returns when not aligned with systemic factors as well.”

Instead, true improvement will likely require “coordinated networks, timely access, and upstream cardiovascular prevention.”

Perhaps just expanding the ability of countries to provide PPCI, on its own, may have diminishing returns when not aligned with systemic factors as well. Ali Malik

Session co-moderator Stéphane Manzo-Silberman, MD (Sorbonne University, Institute of Cardiology—Hôpital Pitié‐Salpêtrière, AP‐HP, Paris, France), observed that the study results are in contrast to “common sense and the common effort [to expand PPCI pursued] for the last 30 years.” She asked if they might arise from variations in age across countries.

Malik said he and his colleagues did attempt to adjust for this, but emphasized their work is “exploratory.” The investigators aim to pursue “a more granular analysis moving forward using registry data” that will reveal nuances on factors such as STEMI versus NSTEMI presentation and the impact of multivessel disease, he added.

Manzo-Silberman also pointed out that differences in treatment delays might be a factor, something that Malik agreed with. He said a prior study done by their group showed that in the United Kingdom, door-to-balloon times have risen alongside an increase in PCI availability.

Despite efforts to reduce residual confounding in this latest study, some still remain, Malik noted. Each country has its own protocol for how to promptly get acute MI patients to the hospital, for example, and what steps the hospital should take upon their arrival.

Dejan Milasinovic, MD (University Clinical Center of Serbia, Belgrade), also a session co-moderator, highlighted how it might be possible to delve more deeply into the relationship between operator volume and mortality by taking a different perspective. “In low-income countries, we know that care is centralized. So you will have this huge hospital, with 10,000 primary PCIs or something like that,” he commented. “In more affluent countries, it is more diffused [with] a lot of hospitals offering primary PCI,” resulting in lower volumes for each hospital and operator.

Thus, in higher-income regions, the link between operator volume and acute MI mortality “could be more clearly seen” when analyzing patterns in the data, said Milasinovic.

Sanjay Sivalokanathan, MD (Mount Sinai Health System, New York, NY), senior author of the study, suggested the findings might reflect trends in health.

“The global rise in cardiometabolic risk factors appears to play a meaningful role in the clinical complexity of patients presenting with acute coronary syndromes. As such, PCI may be challenging in certain settings, highlighting the importance of operator experience and advanced interventional strategies,” he said in an ESC press release. “These developments emphasize the need for collaborative, multidisciplinary approaches, while prevention remains the cornerstone of reducing the overall burden of cardiovascular disease and associated mortality.”

Subsequent analyses will assess factors such as the timing of the procedure in relation to symptom onset, variations in practice across centers and countries, and patient characteristics.