Coronary Stent Thrombosis in COVID-19 Patients: A Systematic Review of Cases Reported Worldwide.

Approximately 5 million percutaneous coronary interventions are performed worldwide annually. Therefore, stent-related complications pose a serious public health concern. Stent thrombosis, although rare, is usually catastrophic, often associated with extensive myocardial infarction or death. Because little progress has been made in outcomes following stent thrombosis, ongoing research is focusing on further understanding the predictors as well as frequency and timing in various patient subgroups. Coronavirus disease-2019 (COVID-19), a viral illness caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), activates inflammatory mechanisms that potentially create a prothrombotic environment and increases the risk of local micro thromboembolism and all types of stent thrombosis. In-stent thrombosis occurrence increased during the COVID-19 pandemic, however, there is still lack of comprehensive studies describing this population. This review and worldwide analysis of coronary stent thrombosis cases related to COVID-19 summarizes all available data.

SARS-COV-2 colonizes coronary thrombus and impairs heart microcirculation bed in asymptomatic SARS-CoV-2 positive subjects with acute myocardial infarction.

BACKGROUND: The viral load of asymptomatic SAR-COV-2 positive (ASAP) persons has been equal to that of symptomatic patients. On the other hand, there are no reports of ST-elevation myocardial infarction (STEMI) outcomes in ASAP patients. Therefore, we evaluated thrombus burden and thrombus viral load and their impact on microvascular bed perfusion in the infarct area (myocardial blush grade, MBG) in ASAP compared to SARS-COV-2 negative (SANE) STEMI patients. METHODS: This was an observational study of 46 ASAP, and 130 SANE patients admitted with confirmed STEMI treated with primary percutaneous coronary intervention and thrombus aspiration. The primary endpoints were thrombus dimension + thrombus viral load effects on MBG after PPCI. The secondary endpoints during hospitalization were major adverse cardiovascular events (MACEs). MACEs are defined as a composite of cardiovascular death, nonfatal acute AMI, and heart failure during hospitalization. RESULTS: In the study population, ASAP vs. SANE showed a significant greater use of GP IIb/IIIa inhibitors and of heparin (p < 0.05), and a higher thrombus grade 5 and thrombus dimensions (p < 0.05). Interestingly, ASAP vs. SANE patients had lower MBG and left ventricular function (p < 0.001), and 39 (84.9%) of ASAP patients had thrombus specimens positive for SARS-COV-2. After PPCI, a MBG 2-3 was present in only 26.1% of ASAP vs. 97.7% of SANE STEMI patients (p < 0.001). Notably, death and nonfatal AMI were higher in ASAP vs. SANE patients (p < 0.05). Finally, in ASAP STEMI patients the thrombus viral load was a significant determinant of thrombus dimension independently of risk factors (p < 0.005). Thus, multiple logistic regression analyses evidenced that thrombus SARS-CoV-2 infection and dimension were significant predictors of poorer MBG in STEMI patients. Intriguingly, in ASAP patients the female vs. male had higher thrombus viral load (15.53 ± 4.5 vs. 30.25 ± 5.51 CT; p < 0.001), and thrombus dimension (4.62 ± 0.44 vs 4.00 ± 1.28 mm2; p < 0.001). ASAP vs. SANE patients had a significantly lower in-hospital survival for MACE following PPCI (p < 0.001). CONCLUSIONS: In ASAP patients presenting with STEMI, there is strong evidence towards higher thrombus viral load, dimension, and poorer MBG. These data support the need to reconsider ASAP status as a risk factor that may worsen STEMI outcomes.

Microthrombi as a Major Cause of Cardiac Injury in COVID-19: A Pathologic Study.

BACKGROUND: Cardiac injury is common in patients who are hospitalized with coronavirus disease 2019 (COVID-19) and portends poorer prognosis. However, the mechanism and the type of myocardial damage associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain uncertain. METHODS: We conducted a systematic pathological analysis of 40 hearts from hospitalized patients dying of COVID-19 in Bergamo, Italy, to determine the pathological mechanisms of cardiac injury. We divided the hearts according to presence or absence of acute myocyte necrosis and then determined the underlying mechanisms of cardiac injury. RESULTS: Of the 40 hearts examined, 14 (35%) had evidence of myocyte necrosis, predominantly of the left ventricle. Compared with subjects without necrosis, subjects with necrosis tended to be female, have chronic kidney disease, and have shorter symptom onset to admission. The incidence of severe coronary artery disease (ie, >75% cross-sectional narrowing) was not significantly different between those with and without necrosis. Three of 14 (21.4%) subjects with myocyte necrosis showed evidence of acute myocardial infarction, defined as ≥1 cm2 area of necrosis, whereas 11 of 14 (78.6%) showed evidence of focal (>20 necrotic myocytes with an area of ≥0.05 mm2 but <1 cm2) myocyte necrosis. Cardiac thrombi were present in 11 of 14 (78.6%) cases with necrosis, with 2 of 14 (14.2%) having epicardial coronary artery thrombi, whereas 9 of 14 (64.3%) had microthrombi in myocardial capillaries, arterioles, and small muscular arteries. We compared cardiac microthrombi from COVID-19-positive autopsy cases to intramyocardial thromboemboli from COVID-19 cases as well as to aspirated thrombi obtained during primary percutaneous coronary intervention from uninfected and COVID-19-infected patients presenting with ST-segment-elevation myocardial infarction. Microthrombi had significantly greater fibrin and terminal complement C5b-9 immunostaining compared with intramyocardial thromboemboli from COVID-19-negative subjects and with aspirated thrombi. There were no significant differences between the constituents of thrombi aspirated from COVID-19-positive and -negative patients with ST-segment-elevation myocardial infarction. CONCLUSIONS: The most common pathological cause of myocyte necrosis was microthrombi. Microthrombi were different in composition from intramyocardial thromboemboli from COVID-19-negative subjects and from coronary thrombi retrieved from COVID-19-positive and -negative patients with ST-segment-elevation myocardial infarction. Tailored antithrombotic strategies may be useful to counteract the cardiac effects of COVID-19 infection.

Acute myocardial infarction and large coronary thrombosis in a patient with COVID-19.

This is a case report of a 60-year-old male, without any cardiovascular risk factor and no cardiac history admitted to hospital with a diagnosis of interstitial pneumonia caused by coronavirus disease 2019 (COVID-19). After 7 days, the blood tests showed a significant rise of inflammatory and procoagulant markers, along with a relevant elevation of high-sensitivity Troponin I. Electrocardiogram and transthoracic echocardiogram (TTE) were consistent with a diagnosis of infero-posterolateral acute myocardial infarction and the patient was transferred to the isolated Cath Lab for primary percutaneous coronary intervention (PCI). The angiography showed an acute massive thrombosis of a dominant right coronary artery without clear evidence of atherosclerosis. Despite the optimal pharmacological therapies and different PCI techniques, the final TIMI flow was 0/1 and after 3 hr the clinical condition evolved in cardiac arrest for pulseless electric activity. Acute coronary syndrome-ST-elevation myocardial infarction is a relevant complication of COVID-19. Due to high levels of proinflammatory mediators, diffuse coronary thrombosis could occur even in patients without cardiac history or comorbidities. This clinical case suggests that coronary thrombosis in COVID-19 patients may be unresponsive to optimal pharmacological (GP IIb-IIIa infusion) and mechanical treatment (PCI).

COVID-19 complicated by ST-segment elevation myocardial infarction in a 29-year-old patient.

We describe a case in which a 29-year-old male with no medical history presented with ST-segment elevation myocardial infarction as his presentation of coronavirus disease. During cardiac catheterization, he was found to have total occlusion of his left anterior descending artery by thrombus. Laboratory testing revealed markedly elevated inflammatory markers as well as evidence of a hypercoagulable state in the setting of severe acute respiratory syndrome coronavirus 2 infection, which was suspected to be the inciting factor for his acute coronary event.