Short-term outcomes among patients with subclinical hypothyroidism undergoing primary percutaneous coronary intervention

Objectives: This study aimed to examine possible associations between previously undiagnosed subclinical hypothyroidism and short-term outcomes and mortality in a sample of Iraqi patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction. Design: This is a prospective observational cohort study. Setting: The study was conducted in a single tertiary referral centre in Baghdad, Iraq. Participants: Thyroid-stimulating hormone and free T4 levels were measured in 257 patients hospitalised with STelevation myocardial infarction who underwent primary percutaneous coronary intervention between January 2020 and March 2022. Main outcome measures: Adverse cardiovascular and renal events during hospitalisation and 30-day mortality were observed. Results: Previously undiagnosed subclinical hypothyroidism was detected in 36/257 (14%) ST-elevation myocardial infarction patients and observed more commonly in females than males. Patients with subclinical hypothyroidism had significantly worse short-term outcomes, including higher rates of suboptimal TIMI Flow (< III) (p =0.014), left ventricular ejection fraction ≤ 40% (p=0.035), Killip class >I (p=0.042), cardiogenic shock (p =0.016), cardiac arrest in the hospital (p= 0.01), and acute kidney injury (p= 0.044). Additionally, 30-day mortality was significantly higher in patients with subclinical hypothyroidism (p= 0.029). Conclusion: Subclinical hypothyroidism previously undiagnosed and untreated had a significant association with adverse short-term outcomes and higher short-term mortality within 30 days compared to euthyroid patients undergoing primary percutaneous coronary intervention. Routine thyroid function testing during these patients' hospitalisation may be warranted.

Symptom-to-balloon time and myocardial blush grade are predictors of left ventricular remodelling after successful primary percutaneous coronary intervention

Introduction: In patients with ST-segment elevation myocardial infarction (STEMI), successful primary percutaneous coronary intervention (PCI) was found to be useful in earlier restoration of TIMI flow 3. However, the incidence of left ventricular (LV) dilatation and remodelling after successful primary PCI is still high. We aimed to determine the independent predictors of LV remodelling after successful primary PCI for patients with first STEMI.Methods: We included 232 STEMI patients treated with primary PCI. Echocardiography was done on the day of PCI and after six months. LV remodelling was defined as ≥ 20% increase in the six-month left ventricular end-diastolic volume (LVEDV). Results: In patients with remodelling, symptom-to-door andsymptom-to-balloon times were significantly longer (p < 0.00001 for each), initial ejection fraction (EF) was significantly lower (p = 0.044), six-month LVEDV, left ventricular end-systolic volume (LVESV) and LVEDV increase were significantly higher, and EF was significantly lower (p < 0.00001 for each). Mean myocardial blush grade (MBG) was significantly lower in patients with remodelling (p < 0.00001). There was a significant positive correlation between LVEDV increase and both symptom-to-balloon time (r = 0.603, p < 0.00001) and symptom-to-door time (r = 0.564, p < 0.00001), and a significant negative correlation between LVEDV increase and MBG (r = ­0.447, p < 0.00001). Logistic regression showed that the independent predictors of LV remodelling were symptom-to-balloon time (p = 0.00068), symptom to door time (p = 0.0013) and MBG (p = 0.0057). Conclusion: Symptom-to-door time, symptom-to-balloon time and MBG were the only significant predictors of LV remodelling