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.

Gender differences in symptoms during 60-second balloon occlusion of the coronary artery.

Previous investigations have demonstrated the presence of gender differences in the symptoms of angina pectoris and acute coronary syndrome. However, most of these investigations have had certain limitations, including being retrospective, an interview-related bias, a various duration of myocardial ischemia, and a lack of multivariate analysis, all of which would have affected the results. Accordingly, we prospectively examined the presence or absence of chest pain and non-chest pain symptoms during a 60-second balloon inflation in the setting of percutaneous coronary intervention, which provides a unique model of transient myocardial ischemia, in 110 men and 80 women with coronary artery disease. Chest pain and/or non-chest pain symptoms (occipital pain, jaw pain, neck/throat pain, shoulder pain, upper arm pain, back pain, and nausea) were observed during the balloon inflation in 72 men and 52 women. In the 124 patients with any symptoms during the balloon inflation, non-chest pain symptoms were more common in women than in men (31% vs 14%, p = 0.02); however, the incidence of chest pain did not differ between the men and women. After adjustment for covariables, including age, body mass index, hypertension, diabetes mellitus, current smoking, previous myocardial infarction, target vessels, ß-blocker use, and calcium antagonist use, female gender remained significantly associated with non-chest pain symptoms (odds ratio 3.3, 95% confidence interval 1.2 to 9.9, p = 0.02). In conclusion, non-chest pain symptoms during the 60-second balloon occlusion of the coronary artery were more common in women than in men, supporting the presence of the gender difference in myocardial ischemic symptoms.

20-Hour preprocedural hydration is not superior to 5-hour preprocedural hydration in the prevention of contrast-induced increases in serum creatinine and cystatin C.

BACKGROUND: Although intravenous hydration with isotonic saline is the standard therapy for the prevention of contrast-induced nephropathy (CIN), there is still insufficient evidence concerning the optimal timing to initiate preprocedural intravenous hydration with isotonic saline. METHODS: This study prospectively compared the contrast-induced increases in serum creatinine and cystatin C between 5-hour preprocedural intravenous hydration with isotonic saline (5h-HS) and 20-hour preprocedural intravenous hydration with isotonic saline (20 h-HS) in 122 patients with renal insufficiency (estimated glomerular filtration rate of 15-60 ml/min/1.73 m(2)) undergoing an elective coronary procedure. The patients were randomly assigned to receive either 5h-HS (n=60) or 20 h-HS (n=62). Serum creatinine and cystatin C were measured at baseline, immediately before contrast exposure, and 24 hours and 48 hours after contrast exposure. The primary end points were the maximal absolute and percent changes in serum creatinine and cystatin C from the baseline up to 48 hours after contrast exposure. RESULTS: The maximal absolute and percent changes in serum creatinine (0.01 ± 0.13 mg/dl vs. -0.03 ± 0.16 mg/dl, p=0.16; 0.87 ± 10.05% vs. -1.50 ± 12.92%, p=0.26; respectively) and cystatin C (-0.05 ± 0.17 mg/l vs. -0.06 ± 0.17 mg/l, p=0.59; -2.94 ± 9.29% vs. -3.46 ± 9.21%, p=0.75; respectively) did not differ between the 2 regimens. CONCLUSIONS: 20 h-HS is not superior to 5h-HS in the prevention of the contrast-induced increases in serum creatinine and cystatin C in patients with renal insufficiency undergoing an elective coronary procedure.

Abnormal P-wave terminal force in lead V1 is associated with cardiac death or hospitalization for heart failure in prior myocardial infarction.

The aim of this study was to clarify the prognostic significance of P-wave terminal force in lead V1 (PTFV1) in patients with prior myocardial infarction (MI). We retrospectively examined 185 patients with prior MI. The primary end point was cardiac death or hospitalization for heart failure. Abnormal PTFV1 was defined as PTFV1 ≥ 40 mm × ms. During a follow-up period of 6.4 ± 2.9 years, 39 patients developed the primary end point. A Kaplan-Meier analysis showed a lower primary event-free rate in 79 patients with abnormal PTFV1 than in 106 patients with normal PTFV1 (P < 0.001). When we classified 79 patients with abnormal PTFV1 into 31 with a purely negative P wave in lead V1 and 48 with a biphasic negative P wave in lead V1, the primary event-free rate did not differ between the two groups of patients. A multivariate Cox regression analysis selected age (hazard ratio (HR) 1.09, 95 % confidence interval (CI) 1.04-1.14, P < 0.001), multivessel coronary disease (HR 2.33, 95 % CI 1.02-5.28, P = 0.04), and abnormal PTFV1 (HR 2.72, 95 % CI 1.24-5.99, P = 0.01) as independent predictors of the primary end point. In conclusion, abnormal PTFV1 is an independent predictor of cardiac death or hospitalization for heart failure in patients with prior MI. The analysis of P waves in lead V1 should provide useful prognostic information in patients with prior MI.

Upright T waves in lead aVR are associated with cardiac death or hospitalization for heart failure in patients with a prior myocardial infarction.

The aim of the present study was to clarify the prognostic significance of upright T waves (amplitude > 0 mV) in lead aVR in patients with a prior myocardial infarction (MI). We retrospectively examined 167 patients with a prior MI. The primary end point was cardiac death or hospitalization for heart failure. During a follow-up period of 6.5 ± 2.8 years, 34 patients developed the primary end point. A Kaplan-Meier analysis showed a lower primary event-free rate in patients with upright T waves in lead aVR than in those with nonupright T waves in lead aVR (P = 0.001). Univariate Cox proportional hazards regression analyses showed that age, gender, chronic kidney disease, anterior wall MI, upright T waves in lead aVR, left ventricular ejection fraction, loop diuretic use, and spironolactone use were significantly associated with the primary end point. A multivariate Cox proportional hazards regression analysis selected age [hazard ratio (HR) 1.10, 95% confidence interval (CI) 1.05-1.16, P < 0.001], upright T waves in lead aVR (HR 3.10, 95% CI 1.23-7.82, P = 0.017), and loop diuretic use (HR 4.61, 95% CI 1.55-13.67, P = 0.006) as independent predictors of the primary end point. In conclusion, the presence of upright T waves in lead aVR is an independent predictor of cardiac death or hospitalization for heart failure in patients with a prior MI. The analysis of T-wave amplitude in lead aVR provides useful prognostic information in patients with a prior MI.

The number of leads with fragmented QRS is independently associated with cardiac death or hospitalization for heart failure in patients with prior myocardial infarction.

BACKGROUND: No information is currently available on the prognostic significance of the number of leads with fragmented QRS (fQRS). The objective of the study was to clarify the prognostic significance of the number of leads with fQRS in prior myocardial infarction (MI). METHODS AND RESULTS: We retrospectively examined 170 patients with prior MI. The primary end point was cardiac death or hospitalization for heart failure. During a mean follow-up period of 6.4 ± 2.9 years, 37 patients developed the primary end point. Univariate Cox proportional hazards regression analyses showed that age, male gender, chronic kidney disease, anterior wall MI, number of leads with fQRS, left ventricular ejection fraction, loop diuretic use, and spironolactone use were significantly associated with the primary end point. A multivariate Cox proportional hazards regression analysis selected age (hazard ratio [HR] 1.09, 95% confidence interval [CI] 1.04-1.14, p<0.001) and the number of leads with fQRS (HR 1.33, 95% CI 1.11-1.60, p=0.002) as predictors of the primary end point. A receiver operating characteristic curve analysis showed that the presence of ≥3 leads with fQRS was most useful for distinguishing between patients with and without the primary end point. A Kaplan-Meier analysis showed a lower primary event-free rate in patients with ≥3 leads with fQRS than in those with <3 leads with fQRS. CONCLUSIONS: The number of leads with fQRS, especially the presence of ≥3 leads with fQRS, is an independent predictor of cardiac death or hospitalization for heart failure in patients with prior MI.