Probable tirofiban-induced thrombotic microangiopathy after stent thrombosis: a case report.

Background: Glycoprotein (GP) IIb-IIIa inhibitors are antithrombotic drugs used in selected patients during and after percutaneous coronary interventions (PCIs), usually as a bail-out in the setting of no-reflow or thrombotic complications. A notorious life-threatening adverse effect of this drug class is immune-mediated drug-induced thrombocytopenia (DITP). Thrombotic microangiopathy (TMA) induced by GP IIb-IIIa inhibitors has never been reported. Case summary: A 72-year-old woman admitted for anterior myocardial infarction treated with primary PCI and stent implantation underwent a first tirofiban infusion as a bail-out strategy. After a new procedure for stent thrombosis, she received a second tirofiban infusion and developed sudden severe thrombocytopenia (platelet count <20 000/µL). Tirofiban was stopped but no observed increase in platelet count. Acute kidney injury due to renal ischaemia and left ventricular thrombosis followed. Unexpectedly, evidence for haemolysis and schistocytosis at peripheral blood smear prompted a diagnosis of TMA. Plasma exchange was immediately started with evidence for initial increase in platelet count, but the patient died due to sudden haemodynamic and respiratory deterioration. Discussion: Tirofiban is known to rarely cause immune-dependent DITP. However, it has never been associated with TMA. This case report not only describes the first case of probable tirofiban-induced TMA, but also highlights the importance of a systematic approach to severe thrombocytopenia, even in the setting of low platelet count from a known DITP-related drug. Treatment of TMA in the difficult context of recent myocardial infarction and stent thrombosis requires a complex interplay between cardiologist, haematologist, transfusionist, and nephrologist, carefully balancing thrombotic and haemorrhagic risk.

Sex-Related Differences in Long-Term Outcomes After Early-Onset Myocardial Infarction.

Importance: There is growing awareness of sex-related differences in cardiovascular risk profiles, but less is known about whether these extend to pre-menopausal females experiencing an early-onset myocardial infarction (MI), who may benefit from the protective effects of estrogen exposure. Methods: A nationwide study involving 125 Italian Coronary Care Units recruited 2,000 patients between 1998 and 2002 hospitalized for a type I myocardial infarction before the age of 45 years (male, n = 1,778 (88.9%). Patients were followed up for a median of 19.9 years (IQR 18.1-22.6). The primary composite endpoint was the occurrence of cardiovascular death, non-fatal myocardial re-infarction or non-fatal stroke, and the secondary endpoint of hospitalization for revascularisation by means of a percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG). Results: ST-elevation MI was the most frequent presentation among both men and women (85.1 vs. 87.4%, p = ns), but the men had a greater baseline coronary atherosclerotic burden (median Duke Coronary Artery Disease Index: 48 vs. 23; median Syntax score 9 vs. 7; both p < 0.001). The primary composite endpoint occurred less frequently among women (25.7% vs. 37.0%; adjusted hazard ratio: 0.69, 95% CI 0.52-0.91; p = 0.01) despite being less likely to receive treatment with most secondary prevention medications during follow up. Conclusions: There are significant sex-related differences in baseline risk factors and outcomes among patients with early-onset MI: women present with a lower atherosclerotic disease burden and, although they are less frequently prescribed secondary prevention measures, experience better long-term outcomes. Trial Registration: 4272/98 Ospedale Niguarda, Ca' Granda 03/09/1998.

Long-term outcomes of early-onset myocardial infarction with non-obstructive coronary artery disease (MINOCA).

BACKGROUND: Acute myocardial infarction with non-obstructive coronary artery disease (MINOCA) is frequent in patients experiencing an early-onset MI, but data concerning its long-term prognosis are limited and conflicting. METHODS: The Italian Genetic Study on Early-onset MI enrolled 2000 patients experiencing a first MI before the age of 45 years, and had a median follow-up of 19.9 years. The composite primary endpoint was cardiovascular (CV) death, non-fatal MI, and non-fatal stroke (MACE); the secondary endpoint was rehospitalisation for coronary revascularisation. RESULTS: MINOCA occurred in 317 patients (15.9%) and, during the follow-up, there was no significant difference in MACE rates between them and the patients with obstructive coronary artery disease (MICAD: 27.8% vs 37.5%; adjusted hazard ratio [HR] 0.79, 95% confidence interval [CI] 0.57-1.09;p = 0.15). The CV death rate was lower in the MINOCA group (4.2% vs 8.4%, HR 0.26, 95%CI 0.08-0.86;p = 0.03), whereas the rates of non-fatal reinfarction (17.3% vs 25.4%; HR 0.76, 95%CI 0.52-1.13;p = 0.18), non-fatal ischemic stroke (9.5% vs 3.7%; HR 1.79, 95%CI 0.87-3.70;p = 0.12), and all-cause mortality (14.1% vs 20.7%, HR 0.73, 95%CI 0.43-1.25;p = 0.26) were not significantly different in the two groups. The rate of rehospitalisation for coronary revascularisation was lower among the MINOCA patients (6.7% vs 27.7%; HR 0.27, 95% CI 0.15-0.47;p < 0.001). CONCLUSIONS: MINOCA is frequent and not benign in patients with early-onset MI. Although there is a lower likelihood of CV death,the long-term risk of MACE and overall mortality is not significantly different from that of MICAD patients.