Lubna Noor

Quantification of diagnostic accuracy using nitrate enhanced Tc-99m sestamibi gated myocardial SPECT in assessing myocardial viability: prospective analysis

The aim of this prospective study was to assess myocardial viability with nitrate-enhanced Tc-99m sestamibi gated single-photon emission computed tomography in patients with known coronary artery disease. We enrolled 48 consecutive patients (39 men, 9 women) aged 24–82 years, with coronary artery disease and history of myocardial infarction. A Tc-99m sestamibi study was conducted at rest as baseline, followed by a nitrate-enhanced study the next day. Of 960 segments analyzed, 244 of 480 in the left anterior descending coronary artery territory showed viability on the baseline study, and 276 were viable according to the nitrate-enhanced study. Similarly, of 192 right coronary segments analyzed, 148 showed viability on the baseline study compared to 153 on the nitrate study. Of 288 left circumflex territory segments analyzed, 206 showed viability on the baseline study compared to 241 on the nitrate study. The overall improvement of viability with the nitrate study was 12.04%. On the gated studies, the overall improvement with nitrate was 2.02%. The gated study also allowed grading of wall motion and thickness. It was concluded that nitrate-augmented Tc-99m sestamibi myocardial imaging significantly improved the detection of hibernating myocardium, with gated images further improving the accuracy of detection in borderline cases.

Impact of stent length and diameter on short term clinical outcomes of drug eluting stents in patients with stable coronary artery disease

Background & Objective: The risk of restenosis and other adverse cardiovascular events with bare-metal stents have increased with smaller stent diameters and longer stent lengths. However, the exact impact of stent size on the short-term outcomes of drug-eluting stent (DES) implantations has not been much classified in Pakistani population. This study was designed to evaluate the impact of size (length and diameter) of Drug Eluting Stents on Clinical outcomes in patient with stable coronary artery disease at three months of implantation in Pakistani Population. Methods: This is a prospective study which was carried out in the Department of Cardiology, Lady Reading Hospital Peshawar from April 2011 and July 2012. All consecutive patients with stable coronary disease undergoing Percutaneous Intervention (PCI) with DES implantation at Cardiology Unit Lady Reading Hospital, were included prospectively. Clinical outcomes (Myocardial infarction [MI], unstable angina[UA], and positive ETT) at three months stratified by 3 tertiles of stent length and diameter each, were measured in patients who underwent PCI with DES for coronary artery lesions. All patients were followed and reassessed after three months from the index procedure. Exercise Tolerance Test(ETT) was performed on every patient and recorded on proforma. Data analysis was done using SPSS software version 16. Results: A total of 376 patients were included prospectively in this study. The mean age was 57±9.313 years. Male patients were 271(72.1%). Mean length of drug eluting stent was 27.313±7.235 mm while mean diameter of stent was 2.90±0.2483mm. There were slightly higher rates of MI, U.A and positive ETT in the longest stent length tertile(>28mm) compared with the shortest stent length tertile (<22mm) at three months, but they were statistically not significant. We also observed that for DES, there was no clear relationship between stent diameter and outcome for any of the clinical outcome variables. Conclusion: In our single-center prospective study, stent length and diameter defined in tertiles, had no impact on the short-term clinical outcomes of DES in patients with stable coronary artery disease.