High-sensitivity troponin T and long-term adverse cardiac events among patients presenting with suspected acute coronary syndrome in Singapore

INTRODUCTION@#Prognostic thresholds for 30-day major adverse cardiac events (MACE) have been studied for high-sensitivity troponin T (hsTnT) in patients with suspected acute coronary syndrome (ACS), but there is limited data on the prognostic performance of hsTnT for one-year MACE.@*METHODS@#We prospectively measured hsTnT (in ng/mL up to two decimal places) at 0, 2 and 7 hours for patients presenting with symptoms suggestive of ACS to our emergency department from March 2010 to April 2013. We assessed the prognostic performance of hsTnT cut-offs for 30-day and one-year MACE, and the utility of delta-hsTnT in predicting MACE.@*RESULTS@#Among 2,444 patients studied, 273 (11.2%) developed MACE (including index MACE) by 30 days and 359 (14.7%) patients developed MACE at one year. The suggested hsTnT cut-off for 30-day MACE was ≥ 10 ng/L at 0 hour (positive predictive value [PPV] 33.5%, negative predictive value [NPV] 94.5%) and 7 hours (PPV 37.3%, NPV 94.5%), and ≥ 20 ng/L at 2 hours (PPV 36.9%, NPV 96.9%). For one-year MACE, the suggested cut-off was also ≥ 10 ng/L at all readings. Plasma hsTnT ≥ 30 ng/L at any reading gave PPV > 54% and NPV > 93% for 30-day MACE. Absolute 0-2 hour and 2-7 hour delta-hsTnT ≥ 10 ng/L gave PPV > 50% for 30-day and one-year MACE.@*CONCLUSION@#Patients with 0-, 2- or 7-hour hsTnT ≥ 30 ng/L and 0-2 hour delta-hsTnT ≥ 10 ng/L had PPV > 50% for 30-day and one-year MACE, and should be investigated thoroughly.

High-grade culprit lesions are a common cause of ST-segment elevation myocardial infarction

<p><b>INTRODUCTION</b>Conventional knowledge holds that the majority of ruptured atherosclerotic plaques causing ST-segment elevation myocardial infarction (STEMI) are found in moderate stenoses that produce < 50% loss of arterial diameter. This study aimed to analyse the culprit lesions in patients who presented with STEMI and underwent primary percutaneous coronary intervention (PPCI) at our institution.</p><p><b>METHODS</b>Patients who underwent PPCI between June 2008 and August 2010 at our institution were included in the analysis. Quantitative coronary angiography was performed for the culprit lesions immediately after antegrade flow was restored by thrombectomy, low-profile balloon predilatation or guidewire crossing.</p><p><b>RESULTS</b>A total of 1,021 patients were included in the study. The mean age was 57 ± 12 years and 85.2% were male. Lesion measurement was done after coronary flow was restored by thrombectomy (73.1%), balloon dilatation (24.1%) and following guidewire passage across the lesion (2.8%). Mean minimal luminal diameter was 1.1 ± 0.5 mm, mean reference vessel diameter was 2.8 ± 0.6 mm, mean diameter stenosis was 61 ± 16% and mean lesion length was 16 ± 6 mm. Most (80.2%) of the culprit lesions had diameter stenoses > 50% (p < 0.01). Although balloon angioplasty was performed in 24.1% of the patients, the majority (64.2%) still had diameter stenoses > 50%. High-grade stenoses (> 50%) were more frequently observed in male patients (p = 0.04).</p><p><b>CONCLUSION</b>Contrary to the existing paradigm, we found that most of the patients with STEMI in our institution had culprit lesions with diameter stenosis > 50%.</p>

Long-term Outcomes of Medical Therapy Versus Coronary Revascularisation in Patients with Intermediate Stenoses Guided by Pressure Wire

<p><b>INTRODUCTION</b>This study aimed to examine the long-term clinical outcomes of coronary fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) in a real-world population in an Asian tertiary centre.</p><p><b>MATERIALS AND METHODS</b>All patients who underwent FFR measurement for intermediate coronary lesions in our centre from June 2002 to December 2009 were enrolled. A threshold of FFR ≤0.75 was used for revascularisation. All the patients were prospectively followed-up for major adverse cardiac events (MACE) of death, myocardial infarction (MI), target vessel revascularisation (TVR) and stent thrombosis.</p><p><b>RESULTS</b>Based on FFR measurement, 368 (57%) patients were treated medically while 278 (43%) underwent revascularisation. At a mean follow-up duration of 29.7 ± 16 months, 53 (14.4%) patients in the medical therapy group and 32 (11.5%) patients in the revascularised group experienced MACE (P = 0.282). There were no statistical differences in all the clinical endpoints between the 2 groups.</p><p><b>CONCLUSION</b>Medical therapy based on FFR measurement is associated with low incidences of MACE at long-term follow-up.</p>