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Background: Patients with occlusion of the left anterior descending coronary artery (LAD) proximal to both the first septal branch and the first diagonal branch may benefit most from early reperfusion therapy due to extensive area at risk. Hypothesis: The aim of the study was to examine whether 12-lead electrocardiograms (ECGs) in the acute phase of acute myocardial infarction (AMI) could identify total occlusion of the LAD proximal to both the first septal and the first diagonal branch. Methods: A 12-lead electrocardiogram was recorded on admission in 128 patients with anterior AMI within 12h from symptom onset. Patients were divided into three groups according to the culprit lesion: 33 patients had total occlusion of the LAD proximal to both the first septal perforator and the first diagonal branch (Group P), in 51 it was proximal to either the first septal perforator or the first diagonal branch (Group D-a), and in 44 it was distal to both the first septal perforator and the first diagonal branch (Group D-b). Results: Sensitivity and specificity of a greater degree of ST-segment depression in lead III than that of ST-segment elevation in lead aVL were 85 and 95%, respectively, which was better than the results derived by all other ECG criteria (p< 0.001). Conclusions: We conclude that a greater degree of ST-segment depression in lead III than that of ST-segment elevation in lead aVL is a useful predictor of proximal LAD occlusion in patients with anterior AMI.

We investigated the effect of reperfusion in patients with complete atrioventricular block within 6 hours after the onset of inferior wall acute myocardial infarction. Early reperfusion may promote the restoration of normal sinus rhythm and effectively reduce infarct size in these patients.

Background Experimental studies suggest that statins promote vascular fibrinolysis, so statin treatment before the onset of acute myocardial infarction (AMI) may result in a smaller infarct size. Methods and Results The study group comprised 310 patients with AMI who received fibrinolysis within 12 h after symptom onset: 39 had received statin pretreatment (statin group) and 271 had not (non-statin group). Initial Thrombolysis In Myocardial Infarction (TIMI) flow grade did not differ between groups. Among 120 patients with initial TIMI flow grade 0/1, achievement of TIMI flow grade >2 after passing the guidewire through the culprit lesion was more frequent in the statin group (70% vs 35%, P=0.03). The final rate of TIMI flow grade 3 was higher in the statin group (95% vs 86%, P=0.11). Area under the curve (AUC) for creatine kinase (CK) was lower in the statin group (55,972±45,934 vs 84,195±84,276 IU · L-1 · h-1, P=0.04). Multivariate analysis revealed statin pretreatment as an independent negative predictor of larger infarct size as defined by the upper tertile of AUC for CK (odds ratio 0.25, 95% confidence interval 0.07-0.91, P=0.035). Conclusion Statin pretreatment may enhance fibrinolysis and reduce infarct size in patients with AMI. (Circ J 2009; 73: 330 - 335)

Background In non-ST-segment elevation acute coronary syndromes (NSTE-ACS), the relation of the level of high-sensitivity C-reactive protein (CRP) to the progression of atherosclerosis remains unclear. Methods and Results The study group comprised 153 patients with NSTE-ACS who underwent percutaneous coronary interventions (PCI) and follow-up (mean interval, 7 months) coronary angiography. Rapid progression was defined as ≥10% diameter reduction of a preexisting stenosis ≥50%, ≥30% diameter reduction of a stenosis

It has been well demonstrated that acute hyperglycemia is associated with high mortality after acute myocardial infarction (AMI). However, optimal plasma glucose (PG) level is not known. The relation between PG and mortality may be different between diabetic and non-diabetic patients. This study consisted of 3,750 patients who were admitted to the 35 hospitals participating to the Japanese Acute Coronary Syndrome Study (JACSS) group within 48 hours after the onset of AMI. PG was measured at the time of hospital admission. In non-diabetic patients, there was a linear relation between PG and in-hospital mortality. Non-diabetic patients with PG ). Diabetic patients with PG 9–10 mmol/L had the lowest mortality (1.9%); both diabetic patients with PG

The impact of ST-segment elevation resolution in lead aVR on outcomes in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) is unclear.Electrocardigrams (ECGs) were recorded on admission and 6 h later in 367 patients with NSTE-ACS. ST-segment deviationor=0.5 mm was considered significant: 92 patients had ST-segment elevation in lead aVR on admission ECG (ST upward arrowaVR), and 275 did not. Among patients with ST upward arrowaVR, 50 had ST resolution, defined as a reduction50% in the degree of ST-segment elevation in lead aVR from admission to 6 h later, and 42 did not. ST upward arrowaVR without ST resolution was associated with older age, greater ST-segment depression in other leads on admission and 6 h later, higher rates of positive troponin T, left main and/or 3-vessel coronary disease, and adverse events such as death, (re)infarction, or urgent revascularization within 30 days after admission. Multivariate analysis showed that ST upward arrowaVR without ST resolution was the strongest independent predictor of death or (re)infarction within 30 days after admission (hazard ratio 5.62, p=0.018).ST upward arrowaVR without ST resolution is a strong predictor of 30-day adverse outcomes and correlates with the extent and severity of coronary artery disease in patients with NSTE-ACS.

SummaryA 40-year-old man was referred to our hospital because of an abnormal shadow on the left cardiac border on the chest roentgenogram at the regular medical health examination without any symptoms. A giant coronary artery aneurysm of left anterior descending artery with a maximum diameter of approximately 50mm was detected with computed tomography and coronary angiography. The patient was treated and followed up medically. Four years later, the size of the coronary artery aneurysm became larger. Then resection of the coronary artery aneurysm and coronary artery bypass grafting were successfully performed. Coronary artery aneurysms are rare in adults and are usually found in association with Kawasaki disease, coronary atherosclerosis, and so on. We also review the literature of giant coronary artery aneurysms exceeding 50mm in diameter.

The use of DDIR mode has been limited since the advent of mode switch in the DDDR mode. In patients with AV block, DDDR is necessary to maintain AV synchrony. However, DDIR mode may still be beneficial for patients with intact AV conduction. The aim of this study was to compare the incidence of ventricular pacing and atrial tachyarrhythmia in DDIR and DDDR with mode switch in a randomized, single-blind, crossover study, and discuss the utility of both modes.Twenty-four patients (8 males) with bradycardia-tachycardia syndrome and no signs of AV block (mean age 70.1 +/- -9.1 years) were enrolled and randomized to DDIR or DDDR modes with the leads placed at the right atrial appendage and right ventricular apex. After 12 weeks, patients were switched to the opposite mode. During the study period, atrial high rate episodes and other pacemaker diagnostic data were collected. Significantly less ventricular pacing was observed in DDIR mode (DDIR versus DDDR; 48.9%, 76.5%, P = 0.0002) and atrial high rate episodes were significantly lower in DDIR mode (DDIR versus DDDR; 1.32, 1.85 per day, P0.05).In patients with sinus node dysfunction and intact AV conduction, DDIR mode may have important implications for simplifying device programming, device longevity, and to avoid atrial tachyarrhythmia.

In inferior acute myocardial infarction (AMI), early complete atrioventricular block (cAVB) has been shown to be associated with poor outcomes; however, prognostic impact of atrial rate during cAVB has yet to be investigated. We studied 331 patients with a first inferior AMI who had TIMI 3 flow of

Recent studies have demonstrated that red blood cell distribution width (RDW) was a novel prognostic marker in patients with ST-segment elevation myocardial infarction (STEMI). Endothelial dysfunction can reflect vascular vulnerability. We hypothesized that elevated RDW level was associated with

The reperfusion therapy including both fibrinolytic therapy and primary percutaneous coronary intervention (PCI) has been established in patients with ST-segment elevation acute myocardial infarction (STEMI). Fibrinolysis has the advantage of universal availability and short time to administration. Because the benefit of fibrinolysis is directly related to the time from symptom onset to treatment as demonstrated in many studies, every effort must be made to minimize any delays between symptom onset and the initiation of a safe and effective reperfusion strategy in patients with STEMI. Although the benefit of fibrinolysis is limited by inadequate reperfusion or reocclusion of the infarct-related artery in a sizable portion of patients, fibrinolysis followed by planned PCI can be one of approaches in patients presenting within 2 or 3 hours from onset of STEMI.

During inferior acute myocardial infarction (AMI), the ECG lead aVR is frequently ignored, and therefore its clinical significance remains unclear. We examined the relation between ST-segment deviation seen in lead aVR on ECGs obtained at hospital admission and myocardial reperfusion in patients who have experienced recanalized inferior AMIs.Retrospective study.A total of 225 patients with inferior AMIs in whom Thrombolysis in Myocardial Infarction grade 3 flow was achieved within 6 h after symptom onset.Patients were classified as follows according to ST-segment deviation in lead aVR on an ECG obtained at hospital admission: group A, 103 patients with no ST-segment depression; group B, 80 patients with ST-segment depression ofor = 1.0 mm; and group C, 42 patients with ST-segment depression of1.0 mm. There were no differences in time from symptom onset to hospital admission or in the culprit lesion among the three groups. The degree of ST-segment elevation in leads II, III, aVF, V5, or V6, the degree of ST-segment depression in leads V1 to V4, and the sum of ST-segment deviation in these leads were lowest in group A and highest in group C. In groups A, B, and C, the incidence of impaired myocardial reperfusion, defined as myocardial blush grade 0/1, was 2%, 23%, and 67%, respectively (p0.001). The sensitivity and negative predictive values of ST-segment depression in lead aVR for impaired myocardial reperfusion were higher than those based on other ECG variables. Multivariate analysis showed that the degree of ST-segment depression in lead aVR was an independent predictor of impaired myocardial reperfusion (odds ratio 8.41; 95% confidence interval, 2.96 to 23.9; p0.001).We conclude that the degree of ST-segment depression in lead aVR is a useful predictor of impaired myocardial reperfusion in patients who have experienced inferior AMIs.

Many studies have shown that ST-segment depression is a strong predictor of poor outcomes in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACSs); however, lead aVR was not considered in these studies. The present study examined the prognostic usefulness of the 12-lead electrocardiogram in combination with biochemical markers in 333 patients with NSTE-ACS. ST-segment deviation of > or =0.5 mm was considered clinically significant. Coronary angiography was performed a median of 3 days after admission in all patients. The primary end point was the composite of death, myocardial infarction, and urgent revascularization at 90 days. ST-segment elevation in lead aVR (odds ratio 13.8, 95% confidence interval 1.43 to 100.9, p = 0.03) and increased troponin T (odds ratio 7.9, 95% confidence interval 1.22 to 123.8, p = 0.04) were the only independent predictors of restricted events (death or myocardial infarction) at 90 days. ST-segment elevation in lead aVR (odds ratio 12.8, 95% confidence interval 4.80 to 33.9, p < 0.0001) and increased troponin T (odds ratio 2.03, 95% confidence interval 1.20 to 4.29, p = 0.04) were also the only independent predictors of adverse events (death, myocardial infarction, or urgent revascularization) at 90 days. When ST-segment status in lead aVR was combined with troponin T, patients with ST-segment elevation in lead aVR and increased troponin T had the highest rates of left main or 3-vessel coronary disease (62%) and 90-day adverse outcomes (47%). In conclusion, our findings suggest that ST-segment status in lead aVR combined with troponin T on admission is a simple and useful clinical tool for early risk stratification in patients with NSTE-ACS.

Background The effects of glucose abnormalities on outcomes after percutaneous coronary intervention (PCI) remain unclear. We examined the association between glucose abnormalities and in-hospital outcome in patients undergoing PCI for acute myocardial infarction (AMI). Methods and Results A total of 849 patients with AMI who were admitted within 12 h after symptom onset and underwent emergency PCI were classified according to the presence or absence of admission hyperglycemia, defined as a blood glucose level on admission of >11 mmol/L and whether they had a history of diabetes mellitus: group 1 (n=504), non-diabetic patients without admission hyperglycemia; group 2 (n=111), diabetic patients without admission hyperglycemia; group 3 (n=87), non-diabetic patients with admission hyperglycemia; and group 4 (n=147), diabetic patients with admission hyperglycemia. Among groups 1, 2, 3 and 4, in-hospital mortality was 2.6, 2.7, 11.5 and 8.8%, respectively (p

BACKGROUND The relationship of changes in blood glucose concentrations after admission to left ventricular (LV) dysfunction in patients with recanalized anterior acute myocardial infarction (AMI) remains unclear. METHODS AND RESULTS Blood glucose concentrations were measured on admission and 24 h after symptom onset in 210 patients with recanalized anterior AMI within 6 h of symptom onset. Of them, 142 had hyperglycemia on admission, defined as a blood glucose >or=8.9 mmol/L, and 68 patients did not. Among the patients with admission hyperglycemia, 49 had persistent hyperglycemia, defined as a blood glucose >or=8.9 mmol/L 24 h after onset, and 93 did not. The incidences of myocardial blush grade of 0/1 after recanalization indicating impaired myocardial perfusion (71%), and peak creatine kinase concentration (5,631+/-2,855 mU/ml) were higher and predischarge LV function (43+/-11%) was lower in patients with persistent hyperglycemia than in those without (p

Several pathological studies have shown that a higher ratio of the serum total cholesterol concentration to the high-density lipoprotein cholesterol concentration (TC/HDL-C ratio) is associated with plaque rupture in patients with acute coronary syndromes. We examined the relationship between the serum total cholesterol concentration and the TC/HDL-C ratio, and clinical and angiographic findings in patients with first acute myocardial infarction.Two hundred eighty patients were classified into quartiles according to the TC/HDL-C ratio measured within 24 hr from symptom onset: 70 patients in the first quartile (group L: mean TC/HDL-C ratio, 3.0), 140 in the second and third quartiles (group M: mean TC/HDL-C ratio, 4.6), and 70 in the fourth quartile (group H: mean TC/HDL-C ratio, 7.5).There were no differences among the three groups with regard to sex, diabetes mellitus or hypertension. Patients in group L were older (66 +/- 9 vs 60 +/- 11, 56 +/- 10 years, p0.01) and had a higher incidence of stable angina before acute myocardial infarction (26% vs 14%, 10%, p0.05) than in patients groups M and H. Although coronary angiograms revealed no difference in the number of diseased vessels among the three groups, extent index indicating the proportion of each coronary segment that appears angiographically abnormal was lowest in group L (0.7 +/- 0.5), followed by group M (1.3 +/- 0.6), and high- est in group H ( 1.7 +/- 0.6, p0.01). The number of segments with calcification and the incidence of calcification in the culprit lesion were higher in group L than in groups M and H.Our findings suggest that the clinical presentations and angiographic appearances differ according to the TC/HDL-C ratio in the acute phase of acute myocardial infarction.

Background: Although anterior acute myocardial infarction (AMI) with ST‐segment elevation in lateral leads is associated with a poor prognosis, the significance of the pattern of lateral ST‐segment elevation has not been examined. Hypothesis: The aim of the study was to examine the relation of the pattern of lateral ST‐segment elevation to myocardial reperfusion and infarct size in patients with AMI. Methods: We studied 111 patients who had a first AMI presenting with anterolateral ST‐segment elevation and Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow of the left anterior descending coronary artery within 6 h from symptom onset. Patients were classified into two groups according to the pattern of lateral ST‐segment elevation on the admission electrocardiogram: Group 1, 42 patients with equivalent or greater ST‐segment elevation in lead I than in lead aVL, and Group 2, 69 patients with lesser ST‐segment elevation in lead I in than in lead aVL. Left ventricular ejection fraction (LVEF) was measured by predischarge left ventriculography. Results: There were no differences between the two groups in age, gender, time from onset to recanalization, culprit lesion, or collateral development. Group 1 patients had a higher probability of impaired myocardial reperfusion as indicated by a myocardial blush grade of 0 or 1 after recanalization, a higher peak creatine kinase level, and a lower LVEF than Group 2 patients (p = 0.0001, respectively). Conclusions: We conclude that equivalent or greater ST‐segment elevation in lead I than in lead aVL is associated with impaired myocardial reperfusion and less myocardial salvage in patients with recanalized AMI who present with anterolateral ST‐segment elevation on the admission electrocardiogram.

Fifty stented lesions in 50 patients with acute myocardial infarction were studied by intravascular ultrasound (IVUS) before and just after stent implantation and at follow-up. Volumetric IVUS analyses revealed that greater peristent positive remodeling after stent implantation was associated with less neointimal proliferation and greater luminal gain at follow-up.

In patients with recanalized acute myocardial infarction (AMI), the relation between the timing of preinfarction angina (PA) and microvascular reperfusion remains unclear. A total of 186 patients (114 with anterior and 72 with inferior AMI) who had total occlusion and TIMI 3 recanalizationor = 6 hours from the onset of AMI were divided into 4 groups according to the time interval between the last episode of PA and the onset of AMI:or = 2 hours (group A, n = 52); 2 to 48 hours (group B, n = 43),or = 48 hours (group C, n = 33), and no PA (group D, n = 58). The angiographic myocardial blush grade, a marker of microvascular reperfusion, was retrospectively assessed immediately after recanalization. There were no differences in baseline characteristics, except for sex among the 4 groups. Myocardial blush grade 3 was more frequent (42% vs 21%, 9%, and 14%) and peak creatine kinase was lower (2659 vs 3455, 4422, and 4622 mU/mL) in group A than in groups B, C, and D (all P0.05). Multivariate analysis showed that PA occurringor = 2 hours before AMI (OR 3.88, P0.05), a smaller summed ST-segment elevation before recanalization (OR 0.84, P0.01), earlier time to recanalization (OR 0.52, P0.05), and interior AMI (OR 4.87, P0.05) were independently associated with adequate microvascular reperfusion. We conclude that PAor = 2 hours before the onset of AMI is independently associated with adequate microvascular reperfusion after recanalization in patients with AMI.

We studied the effect of preinfarction angina on in-hospital outcomes after percutaneous coronary intervention for anterior and nonanterior acute myocardial infarction. Beneficial effects of preinfarction angina on infarct size and in-hospital outcome are evident in patients with anterior infarction, but not in those with nonanterior infarction.

Resolution of ST-segment elevation (ST resolution) after reperfusion therapy has been shown to correlate with improved left ventricular (LV) function in patients with acute myocardial infarction (AMI). However, not all patients with ST resolution have preserved LV function. We evaluated the clinical significance of ST resolution in 129 patients with anterior wall AMI who underwent successful coronary recanalization within 6 hours after symptom onset by studying the relation to myocardial blush grade, another angiographic marker of myocardial reperfusion. A reduction ofor =50% in ST-segment elevation after recanalization was defined as ST resolution. Ninety-eight patients had ST resolution and 31 patients did not. Patients with ST resolution were subdivided into 2 groups according to myocardial blush grade after recanalization: 67 patients with blush grade 2 or 3, and 31 with blush grade 0 or 1. The QRS score after recanalization was higher (5.9 +/- 1.9 vs 3.4 +/- 2.0, p0.01) and predischarge LV ejection fraction was lower (39 +/- 8% vs 57 +/- 9%, p0.01) in patients with blush grade 0 or 1 than in those with blush grade 2 or 3. However, the QRS score after recanalization and the predischarge LV ejection fraction were similar in patients who had ST resolution with blush grade 0 or 1 and in those without ST resolution. Our findings suggest that ST resolution after recanalization does not consistently predict myocardial salvage in patients with anterior AMI.

Patients with an anterolateral acute myocardial infarction (AMI) have a worse prognosis, and those with additional inferolateral wall involvement might be higher risk because of more extensive area at risk. Lead -aVR obtained by inversion of images in lead aVR has been reported to provide useful information for inferolateral lesion.We examined the relation between ST-segment deviation in lead aVR on admission electrocardiogram (ECG) and left ventricular function in 105 patients with an anterolateral AMI undergoing successful reperfusionor = 6 hours after onset. Patients were classified according to ST-segment deviation in lead aVR on admission ECG: group A, 23 patients with ST elevation ofor = 0.5 mm; group B, 47 patients without ST deviation; and group C, 35 patients with ST depression ofor = 0.5 mm.There were no differences among the 3 groups in age, sex, or site of the culprit lesion. In groups A, B, and C, the peak creatine kinase level was 3661 +/- 1428, 4440 +/- 1889, and 6959 +/- 2712 mU/mL, and the left ventricular ejection fraction (LVEF) measured by predischarge left ventriculography was 54% +/- 9%, 48% +/- 7%, and 37% +/- 9%, respectively(P.01). During hospitalization, congestive heart failure occurred more frequently in group C than in groups A or B (P.05). ST-segment depression in lead aVR had a higher predictive accuracy than other ECG findings in identifying patients with predischarge LVEFor = 35%.We conclude that in patients with an anterolateral AMI, ST-segment depression in lead aVR on admission ECG is useful for predicting larger infarct and left ventricular dysfunction despite successful reperfusion.

Although early peak creatine kinase activity (peak CK) is considered a reliable marker of coronary reperfusion in patients with acute myocardial infarction (AMI), whether early peak CK indicates good myocardial salvage is unclear. Moreover, some patients have late peak CK despite successful reperfusion, and its clinical implication remains to be elucidated.We examined the association of the time to peak CK with predischarge left ventricular function in 124 patients with a first AMI who had successful reperfusion within 6 hours from symptom onset. Patients were classified according to the time from reperfusion to peak CK: group A, 61 patients with peak CK6 hours; group B, 42 with peak CK from 6 to 12 hours; and group C, 21 with peak CK12 hours. There were no differences among the 3 groups in age, sex, method of reperfusion, time from symptom onset to reperfusion, collateral circulation, or the extent of risk area estimated by number of leads with ST-segment elevation. Left ventricular ejection fraction measured by predischarge left ventriculography was lowest in group A, followed by group B, and highest in group C (median values, 43%, 52%, and 60%, P.01). Left ventricular dysfunction (left ventricular ejection fractionor = 40%) occurred in 26 (43%) patients in group A, 8 (19%) in group B, and none in group C (P.01).We conclude that compared with early peak CK, late peak CK consistently reflects good myocardial salvage in patients with anterior AMI who had successful reperfusion within 6 hours from symptom onset.

Cardiac function is improved by optimizing the atrioventricular (AV) delay. An automatic optimizing function of AV delay may be necessary to achieve the most favourable haemodynamic state in paced patients. The QT interval may change when cardiac function is improved by optimizing the AV delay. The QT or stimulus-T interval is used as a sensor for rate-responsive pacemakers. Evoked (e) QT interval is measured as the time duration from the ventricular pace pulse (stimulus) and the T-sense point that is the steepest point of the intracardiac T wave (stimulus-T interval). The relationship between AV delay, eQT interval and cardiac function was studied in 10 patients (73 +/- 10 (SD) years old) with an implanted stimulus-T-driven DDDR pacemaker. Cardiac output (CO) and pulmonary capillary wedge pressure (PCWP) were measured by Swan-Ganz catheter. The AV delay was prolonged stepwise by 30 ms. Electrocardiogram event markers which indicated ventricular spike and sensed T wave were recorded, and the interval between two event markers was measured as eQT interval. When AV delay was changed from 240 ms to the AV delay at which CO was maximal (172 +/- 33 ms), eQT interval prolonged from 346 +/- 60 to 353 +/- 62 ms (P < 0.01). There was a significant positive correlation between the optimal AV delay at which CO was maximal (172 +/- 33 ms) and the optimal AV delay which was predicted from the maximum eQT interval (179 +/- 37 ms, r = 0.92, P < 0.001). When AV delay was changed from 240 ms to the predicted optimal AV delay, CO increased from 4.2 +/- 0.7 to 4.5 +/- 0.81.min-1 (P < 0.001) and PCWP was decreased from 7.1 +/- 4.0 to 5.7 +/- 3.1 mmHg (P < 0.05). In conclusion, the optimal AV delay can be predicted from the eQT interval which is sensed by an implanted pacemaker. Automatic setting of the optimal AV delay may be achieved by the QT sensor of an implanted pacemaker.

Although sinus node recovery time (SNRT) assessment by the overdrive suppression test (ODST) is important in detecting sick sinus syndrome (SSS), its sensitivity is still inadequate. We have evaluated the effect of intravenous injection (i.v.) of disopyramide phosphate (DP) in ODST. The subjects were 30 SSS patients (64.9 +/- 10.0SDyears old). If SNRT was2,000 ms or the corrected SNRT (CSNRT) was1,000 ms, ODST was repeated after DP i.v. (2 mg. kg(-1),or = 100 mg in total). Eleven normal subjects (59.3 +/- 9.0 years old) were also studied. Although SNRT was2,000 ms or the CSNRT was1,000 ms in 13 of the 30 SSS patients (43%), SNRT was prolonged from 1,510 +/- 300ms to 3,400 +/- 1,160 ms (P0.01), and CSNRT from 510 +/- 190 to 2,470 +/- 1,470 ms (P0.01) after DP i.v. in these patients. Thus, SNRT wasor = 2,000 ms and the CSNRT wasor = 1,000 ms in 27 of 30 SSS patients (90%) after DP i.v. Using a combination of overdrive suppression and intravenous injection of disopyramide phosphate, the corrected sinus node recovery time was diagnostic (525 ms) in 29 of the 30 patients (97%). In contrast, SNRT and CSNRT were shortened in the normal subjects during ODST after DP i.v. (P0.01). The plasma concentration of DP estimated in nine patients was 4.1 +/- 1.0 microg.ml(-1). No serious side effect occurred. ODST employing DP i.v. is safe and seems to be highly effective in diagnosing SSS.

To identify ways to decrease the risk of out-of-hospital cardiac arrest (CA) caused by an acute coronary syndrome, we examined factors associated with the development of CA > or = 1 hour after symptom onset. Multivariate analysis revealed that a low level of physical activity, a history of diabetes mellitus, and a history of unstable angina are associated with out-of-hospital CA occurring > or = hour after symptom onset.

The efficacy of a short atrioventricular (AV) delay in patients with dilated cardiomyopathy has been reported, but there are deleterious effects of right ventricular pacing. Diastolic mitral regurgitation (MR) is observed in patients with elevated left ventricular end-diastolic pressure and can be induced by prolonging the AV delay in patients with DDD pacemakers. The critical PQ interval that induces diastolic MR may represent the upper limit of the optimal PQ interval. The efficacy of AV sequential pacing and diastolic MR were studied in 11 patients (68.3+/-13.7 (SD) years old) with intrinsic AV conduction and with implanted DDD pacemakers. Cardiac output (CO) and pulmonary capillary wedge pressure (PCWP) were measured by Swan-Ganz catheter and transmitral flow was recorded by pulsed Doppler echocardiography. AV delay was prolonged stepwise by 25 ms starting from 65 ms. Pacing rate was fixed at 70-80 beats/min. In 6 of the 11 patients, diastolic MR was observed under atrial pacing and the critical PQ interval for the appearance of diastolic MR was 0.22+/-0.04 s. CO was increased from 3.8+/-0.8 to 4.3+/-0.9 L/min (p0.05) and PCWP was decreased from 7.5+/-2.8 to 5.5+/-1.6 mmHg (p0.05) by shortening the AV delay till the diastolic MR disappeared. On the other hand, in 5 of the 11 patients, diastolic MR was not observed, and CO (4.2+/-0.5 to 4.3+/-0.5L/min, ns) and PCWP (5.8+/-4.6 to 5.4+/-3.9 mmHg, ns) were not improved by AV sequential pacing. In conclusion, cardiac function may be improved by AV sequential pacing and setting the AV delay under the critical PQ interval for the appearance of diastolic MR when the diastolic MR is observed. However, AV sequential pacing may be either ineffective or even deleterious for patients in whom diastolic MR is not observed.

The pathogenic mechanisms underling the onset of acute myocardial infarction (AMI) have not been fully clarified. Recent observations of inflammatory cell infiltration in unstable coronary plaques suggest that inflammation may play an important role in the pathogenesis of AMI. Plasma levels of C-reactive protein (CRP), a sensitive marker of inflammation, start to rise at least 6 hours after the onset of AMI. Therefore, CRP levels within the first 6 hours after the onset of AMI more likely reflect preexisting inflammatory activity rather than myocardial cell necrosis. We examined the relation between CRP levels on admission and the onset pattern of AMI to estimate the contribution of inflammation to the pathogenesis of AMI.

The implication of the shape of ST elevation in the acute phase of myocardial infarction (MI) remains unclear.We examined the relation between the shape of ST elevation and infarct size in 77 patients who had a first acute anterior MI with successful reperfusion within 6 hours from symptom onset. A 12-lead electrocardiogram was recorded immediately before reperfusion confirmed by coronary angiography. The shape of ST elevation in lead V3 was classified into 3 types: concave type (n = 24), straight type (n = 41), and convex type (n = 12). For concave type, straight type, and convex type, a median value of peak creatine kinase was 2287, 4371, and 5322 mU/mL, and left ventricular ejection fraction measured by left ventriculography at discharge (14 days after MI) was 58%, 48%, and 41% (P.05; concave type versus the other 2 types), respectively. A multivariate logistic regression model demonstrated that the concave type of ST elevation was a strong predicting factor for preserved left ventricular function (left ventricular ejection fraction/=50% at discharge; odds ratio 6.2, 95% confidence interval 1.6 to 20.8, P =.019).In patients with reperfused acute anterior MI, left ventricular function was excellent in patients with concave type, intermediate in those with straight type, and relatively poor in those with convex type ST elevation at discharge. This simple classification is useful for predicting left ventricular function at discharge.

Background: Calcified lesions sometimes cause stent underexpansion which increase the risk of stent thrombosis and target lesion revascularization after percutaneous coronary intervention (PCI). Rotational atherectomy (RA) plays an important role to facilitate the dilation or stenting of these lesions. Optical coherence tomography (OCT) is a new imaging modality that visualize calcium component without signal attenuation. The aim of this study was to examine the effects of RA and subsequent balloon angioplasty on calcified coronary plaques using OCT. Methods: From October 2011 to December 2012, a total of 17 calcified lesions requiring RA in patients with CAD were interrogated by FD-OCT. In all patients, OCT images just after atherectomy and after balloon angioplasty (before stent implantation) were analyzed to assess calcium component. The thickness of the calcium component was measured at its thinnest part. The arc, thickness of the calcium component, and the lumen area in each segment as determined by OCT were measured at 1-mm intervals. The incidence of calcium cracks after balloon angioplasty following RA was also assessed by OCT. Results: A total of 328 segments in 17 lesions were analyzed. Calcium cracks were observed in 138 segments (42%) in 14 patients (82%). The segment with calcium cracks after angioplasty had smaller lumen area (3.39±1.43 vs 3.92±1.78 mm2, P