Features of electrocardiogram in patients with stenosis of the proximal right coronary artery

BACKGROUND/AIMS: Prediction of lesions of the proximal right coronary artery (pRCA) through electrocardiogram (ECG) is very important because pRCA occlusion has many complications and a high mortality rate, which has frequently been related with right ventricular infarction. The purpose of this study was to devise a screening tool that takes into account multiple leads from a 12-lead ECG to predict the pRCA lesion. METHODS: A hundred and fifty-eight patients who were diagnosed as acute coronary syndrome and had a pure lesion of RCA or left circumf lex artery (LCX) by ECGs and angiographic findings were enrolled retrospectively. Forty-eight patients with a pure pRCA occlusion were compared to a control group of 110 patients who were diagnosed as having either a pure mid to distal RCA lesion (57 patients) or a pure LCX lesion (53 patients). RESULTS: ECGs of patients in the pRCA group showed more prominent ST depression in lead I (p = 0.001) and ST elevation in V1 (p = 0.002) than in the control group. The combination of ST depression (≤ 0 mm) in I and ST elevation (> 0.5 mm) in V1 was the best diagnostic tool (area under the curve, 0.84). CONCLUSIONS: ST changes in leads V1 and I allow more accurate prediction of pRCA occlusion than other criteria, such as the difference between ST elevation of leads II and III or vector direction and amplitude. These variables could help to screen for right ventricular infarction before performing reverse ECG and predicting prognosis.

Is Intravenous Contrast-Enhanced Computed Tomography Dangerous in Patients with Elevated Serum Creatinine?

PURPOSE: Although computed tomography (CT) with contrast media (CM) is often performed in patients with renal failure, caution has been exercised due to the supposed risk of contrast-induced nephropathy (CIN). The aim of this study was to examine to true impact of CT with CM on patients with elevated serum creatinine (sCr) levels. METHODS: A total of 216 patients with renal insufficiency who underwent intravenous (IV) contrast CT, with available sCr measurements before and after CT, between January 2008 and March 2012 were included. Patient demographic, biochemical, physiological, and CM data, fluid and drug administration, causes and prognostic factors of CIN, and previously described risk factors were analyzed. RESULTS: The most significant risk factor of CIN in patients with elevated sCr was an acute disease causing pre-renal acute kidney injury (AKI) (p=0.01, odds ratio 4.2), typically related to severe sepsis and septic shock (p<0.001). The factors of fatality related to sCr at day 14 were acute diseases causing pre-renal AKI (p<0.001, p=0.001 respectively). Iodine amounts, chronic kidney disease, prophylactic treatments, and other supposed risk factors did not greatly affect the risk of CIN. CONCLUSION: Although risk factors of CIN are not fully understood, CIN in patients with elevated sCr may be the result of acute progressing diseases, such as AKI in severe sepsis. CIN following IV contrast CT may therefore be less serious than previously thought. We suggest that CT can be performed when needed, even in patients with elevated sCr.