Reliability of ST-segment shifts in the synthesized V3R-V5R leads after coronary balloon inflations during percutaneous coronary intervention.

Obtaining a right-chest electrocardiogram is essential for diagnosing concomitant right ventricular infarction in patients with inferior wall acute myocardial infarctions. A software program to synthesize right-chest electrocardiographic waveforms from 12-lead electrocardiographic waveforms is available in Japan. However, its reliability has not been fully investigated. Accordingly, the aim of this study was to examine the reliability of ST-segment shifts in the synthesized V3R to V5R leads. ST-segment shifts in actual and synthesized V3R to V5R leads were compared during the last 10 seconds of 131 balloon inflations while performing elective percutaneous coronary intervention in 56 patients with coronary artery disease. ST-segment shifts in the actual and synthesized V3R, V4R, and V5R leads were correlated (r = 0.96, p <0.001, r = 0.94, p <0.001, and r = 0.91, p <0.001, respectively). A Bland-Altman analysis showed that the bias between ST-segment shifts in the actual and synthesized V3R to V5R leads was -3.1, -5.4, and -4.2 µV, respectively, while the limits of agreement between the ST-segment shifts in the actual and synthesized V3R to V5R leads were -59.2 to 52.9, -61.9 to 51.1, and -59.7 to 51.3 µV, respectively. The κ coefficients for ST-segment elevation of ≥50 and ≥100 µV in the actual and synthesized V3R, V4R, and V5R leads were 0.83 and 0.81, 0.66 and 0.83, and 0.57 and 0.80, respectively. In conclusion, these results indicate that ST-segment shifts in the synthesized V3R to V5R leads have acceptable reliability, suggesting that synthesized right-chest electrocardiography can be used to diagnose concomitant right ventricular infarction in patients with inferior wall acute myocardial infarctions.

Antithrombin deficiency in three Japanese families: one novel and two reported point mutations in the antithrombin gene.

INTRODUCTION: Inherited antithrombin (AT) deficiency is associated with a predisposition to familial venous thromboembolic disease. We analyzed the AT gene in three unrelated patients with an AT deficiency who developed thrombosis. MATERIALS AND METHODS: We analyzed the SERPINC1 gene in three patients. Additionally, we expressed the three mutants in the COS-1 cells and compared their secretion rates and levels of AT activity with those of the wild-type (WT). RESULTS: We identified three distinct heterozygous mutations of c.2534C>T: p.56Arginine → Cysteine (R56C), c.13398C>A: p.459Alanine → Aspartic acid (A459D) and c.2703C>G: p.112 Proline → Arginine (P112R). In the in vitro expression experiments, the AT antigen levels in the conditioned media (CM) of the R56C mutant were nearly equal to those of WT. In contrast, the AT antigen levels in the CM of the A459D and P112R mutants were significantly decreased. The AT activity of R56C was decreased in association with a shorter incubation time in a FXa inhibition assay and a thrombin inhibition-based activity test. However, the AT activity of R56C was comparable to that of WT when the incubation time was increased. CONCLUSIONS: We concluded that the R56C mutant is responsible for type II HBS deficiency. We considered that the A459D and P112R mutants can be classified as belonging to the type I AT deficiency.

ST-segment deviation in lead aVR on admission is not associated with left ventricular function at predischarge in first anterior wall ST-segment elevation acute myocardial infarction.

Previous studies have shown that the analysis of ST-segment deviation in lead aVR on admission provides useful information on angiographic coronary anatomy and risk stratification in acute coronary syndromes. However, the association between ST-segment deviation in lead aVR on admission and left ventricular (LV) function has not been fully investigated in anterior wall acute ST-segment elevation myocardial infarction. In this study, 237 patients with first anterior wall acute ST-segment elevation myocardial infarction were examined. The patients were divided into the following 3 groups according to ST-segment deviation in lead aVR on admission: 85 with ST-segment elevation ≥0.5 mm (group A), 106 without ST-segment deviation (group B), and 46 with ST-segment depression ≥0.5 mm (group C). LV ejection fractions at predischarge were compared among the 3 groups. Among the 3 groups, there were significant differences in the prevalences of proximal left anterior descending coronary artery (LAD) occlusion (group A 75.3%, group B 56.6%, group C 45.7%, p = 0.002), long LAD (group A 27.1%, group B 31.1%, group C 56.5%, p = 0.002), and good collaterals to the LAD (group A 40.0%, group B 25.4%, group C 17.4%, p = 0.01). LV ejection fractions at predischarge did not differ among the 3 groups (group A 56.4 ± 12.5%, group B 56.9 ± 12.7%, group C 53.3 ± 12.2%, p = 0.26). On a multiple regression analysis, establishment of Thrombolysis In Myocardial Infarction grade 3 flow, proximal LAD occlusion, and long LAD were associated with the LV ejection fraction at predischarge. In conclusion, ST-segment deviation in lead aVR on admission is not associated with LV function at predischarge in first anterior wall acute ST-segment elevation myocardial infarction.

Washout rate of cardiac iodine-123 metaiodobenzylguanidine is high in chronic heart failure patients with central sleep apnea.

BACKGROUND: The association between sleep-disordered breathing (SDB) assessed by polysomnography and cardiac sympathetic nerve activity (SNA) assessed by cardiac iodine-123 metaiodobenzylguanidine (123I-MIBG) imaging has not been investigated in patients with chronic heart failure (CHF). METHODS AND RESULTS: We performed cardiac 123I-MIBG scintigraphy and overnight polysomnography in 59 patients with stable CHF. The patients were classified into the 3 groups: 19 with no or mild SDB (NM-SDB, apnea-hypopnea index <15); 21 with central sleep apnea (CSA), and 19 with obstructive sleep apnea (OSA). The cardiac washout rate (WR) of 123I-MIBG was obtained from initial and delayed planar 123I-MIBG images. The WR was higher in patients with CSA (54.2 + or - 11.6%) than in those with OSA (37.9 + or - 8.6%, P < .05) or NM-SDB (40.8 + or - 8.8%, P < .05). The WR correlated positively with central apnea index (rho = 0.40, P = .002). A stepwise multiple regression analysis selected CSA and plasma brain natriuretic peptide levels as independent variables associated with the WR. CONCLUSIONS: The WR was higher in CHF patients with CSA than in those with OSA or NM-SDB, and CSA was independently associated with the WR, suggesting a link of CSA to increased cardiac SNA in CHF.

Efficacy of single-bolus administration of sodium bicarbonate to prevent contrast-induced nephropathy in patients with mild renal insufficiency undergoing an elective coronary procedure.

We sought to clarify whether a single-bolus intravenous administration of sodium bicarbonate in addition to hydration with sodium chloride prevents contrast-induced nephropathy (CIN). One hundred forty-four patients with mild renal insufficiency (serum creatinine >1.1 to <2.0 mg/dl) undergoing an elective coronary procedure were randomly assigned to the following 2 groups: standard hydration with sodium chloride plus single-bolus intravenous administration of sodium bicarbonate (20 mEq) immediately before contrast exposure (group A, n = 72) and standard hydration alone (group B, n = 72). The primary end point was development of CIN, defined as an increase >25% or >0.5 mg/dl in serum creatinine within 3 days after the procedure. Incidence of the primary end point was lower in group A than in group B (1.4% vs 12.5%, p = 0.017). Incidence of adverse clinical events (acute pulmonary edema, acute renal failure requiring dialysis, and death within 7 days of procedure) did not differ between the 2 groups (0% vs 1.4%). In conclusion, single-bolus intravenous administration of sodium bicarbonate in addition to standard hydration can more effectively prevent CIN than standard hydration alone in patients with mild renal insufficiency undergoing an elective coronary procedure.

Incidental detection of cancers and other non-cardiac abnormalities on coronary multislice computed tomography.

The investigators prospectively examined 625 consecutive patients who underwent coronary multislice computed tomography (MSCT) for suspected coronary artery disease (CAD) and evaluated the presence or absence of cancers and other noncardiac abnormalities on the original transverse sectional images of MSCT. Eight patients with known cancers were excluded from the analysis. The remaining 617 patients (344 men, 273 women; mean age 66 +/- 12 years) were analyzed. Cancers were found in 7 patients (1.13%) on the multislice computed tomographic images, including 4 lung cancers (0.65%), 2 thyroid cancers (0.32%), and 1 hepatic cancer (0.16%). In addition, nonmalignant abnormalities (nodules, tumors, or lymphadenopathies) were also found in 142 patients (23.01%), consisting of 58 postinflammatory lung nodules (9.40%), 49 hepatic cysts or hemangiomas (7.94%), 18 benign thyroid tumors (2.92%), 12 mediastinal lymphadenopathies (1.94%), 4 benign mammary gland tumors (0.65%), and 1 esophageal submucosal tumor (0.16%). In conclusion, cancers and other noncardiac abnormalities are often found in patients who undergo coronary MSCT for suspected CAD. Because patients who undergo coronary MSCT for suspected CAD are mostly elderly and therefore may have unrecognized cancers or other noncardiac abnormalities, care should thus be taken not to overlook these abnormalities when analyzing the multislice computed tomographic images.