Effects of adjunctive balloon angioplasty after intravascular ultrasound-guided optimal directional coronary atherectomy: the result of Adjunctive Balloon Angioplasty After Coronary Atherectomy Study (ABACAS).

OBJECTIVES: This study was conducted to evaluate: 1) the effect of adjunctive percutaneous transluminal coronary angioplasty (PTCA) after directional coronary atherectomy (DCA) compared with stand-alone DCA, and 2) the outcome of intravascular ultrasound (IVUS)-guided aggressive DCA. BACKGROUND: It has been shown that optimal angiographic results after coronary interventions are associated with a lower incidence ofrestenosis. Adjunctive PTCA after DCA improves the acute angiographic outcome; however, long-term benefits of adjunctive PTCA have not been established. METHODS: Out of 225 patients who underwent IVUS-guided DCA, angiographically optimal debulking was achieved in 214 patients, then theywere randomized to either no further treatment or to added PTCA. RESULTS: Postprocedural quantitative angiographic analysis demonstrated an improved minimum luminal diameter (2.88 +/- 0.48 vs. 2.6 +/- 0.51 mm; p = 0.006) and a less residual stenosis (10.8% vs.15%; p = 0.009) in the adjunctive PTCA group. Quantitative ultrasound analysis showed a larger minimum luminal diameter (3.26 +/- 0.48 vs. 3.04 +/- 0.5 mm; p < 0.001) and lower residual plaque mass in the adjunctive PTCA group (42.6% vs. 45.6%; p < 0.001). Despite the improved acute findings in the adjunctive PTCA group, six-month angiographic and clinical results were not different. The restenosis rate (adjunctive PTCA 23.6%, DCA alone 19.6%; p = ns) and target lesion revascularization rate (20.6% vs. 15.2%; p = ns) did not differ between the groups. CONCLUSIONS: With IVUS guidance, aggressive DCA can safely achieve optimal angiographic results with low residual plaque mass, and this was associated with a low restenosis rate. Although adjunctive PTCA after optimal DCA improved the acute quantitative coronary angiography and quantitative coronary ultrasonography outcomes, its benefit was not maintained at six months.

Impact of tranilast on restenosis after coronary angioplasty: tranilast restenosis following angioplasty trial (TREAT).

BACKGROUND: Tranilast is an antiallergic drug that suppresses the release of cytokines such as platelet-derived growth factor, transforming growth factor-beta1, and interleukin-1beta and prevents keloid formation after skin injury. Treatment with this drug reduced the restenosis rate after percutaneous transluminal coronary angioplasty in a preliminary study. METHODS AND RESULTS: We conducted a multicenter, randomized, double-blind, placebo-controlled trial. A total of 255 patients with 289 lesions were randomly assigned to treatment with the oral administration of 600 mg/d tranilast, 300 mg/d tranilast, or a placebo for 3 months after successful angioplasty. Angiographic follow-up was done at 3 months, and a clinical follow-up examination was performed at 12 months. Two hundred ten (72.7%) lesions of 188 (73.7%) of the patients met the criteria and were eligible for the assessment of restenosis. The restenosis rates defined as >/=50% loss of the initial gain were 14.7% in the 600 mg/d tranilast group, 35.2% in the 300 mg/d tranilast group, and 46.5% in the placebo group (P <. 0001 for 600 mg/d tranilast vs placebo). The restenosis rates defined as percent diameter stenosis of >/=50% at follow-up were 17. 6% in the 600 mg/d tranilast group, 38.6% in the 300 mg/d tranilast group, and 39.4% in the placebo group (P =.005 for 600 mg/d tranilast vs placebo). CONCLUSIONS: The oral administration of 600 mg/d of tranilast for 3 months markedly reduced the restenosis rate after percutaneous transluminal coronary angioplasty.

Stromelysin promoter 5A/6A polymorphism is associated with acute myocardial infarction.

BACKGROUND: Rupture of the fibrous cap of an atherosclerotic plaque is a key event that predisposes to acute myocardial infarction (AMI). Matrix metalloproteinases (MMPs) may contribute to weakening of the cap, which favors rupture. Stromelysin, a member of MMP family, is identified extensively in human coronary atherosclerotic lesions. It can degrade most of the constituents of extracellular matrix as well as activating other MMPs, which suggests that it may play an important role in plaque rupture. Recently, a common variant (5A/6A) in the promoter of the stromelysin gene has been identified. The 5A/6A polymorphism could regulate the transcription of the stromelysin gene in an allele-specific manner. METHODS AND RESULTS: To investigate the relation between the 5A/6A polymorphism in the promoter of the stromelysin gene and AMI, we conducted a case-control study of 330 AMI patients and 330 control subjects. The prevalence of the 5A/6A+5A/5A genotype was significantly more frequent in the patients with AMI than in control subjects (48.8% vs 32.7%, P<0.0001). In logistic regression models, the odds ratio of the 5A/6A+5A/5A was 2.25 (95% CI, 1.51 to 3.35). The association of 5A/6A polymorphism with AMI was statistically significant and independent of other risk factors. CONCLUSIONS: The 5A/6A polymorphism in the promoter of the stromelysin gene is a novel pathogenetic risk factor for AMI.

Comparison of results of intracoronary implantation of the Plamaz-Schatz stent with conventional balloon angioplasty in chronic total coronary arterial occlusion.

We compared angiographic and clinical outcomes after successful revascularization of chronic total coronary arterial occlusion with the placement of the Palmaz-Schatz stent (43 patients) and conventional balloon angioplasty (53 patients). After the procedure, the coronary stent led to a greater minimal lumen diameter than conventional balloon angioplasty (2.6 vs 1.7 mm, p < 0.001), resulting in a smaller residual stenosis (6.5% vs 36.7%, p < 0.001). At 6-month follow-up, there was no significant difference in late loss between the groups, resulting in a larger minimal lumen diameter at follow-up in the stent group (1.8 vs 1.1 mm, p < 0.001). The incidence of restenosis was lower in the stent group (27.9% vs 56.6%, p < 0.005). The frequency of the combination of myocardial infarction and coronary artery bypass graft surgery tended to be less in the stent group (2.3% vs 11.3%, P = 0.09). Placement of the Palmaz-Schatz stent improved left ventricular ejection fraction by 26% in patients who had reduced left ventricular function (p < 0.05), but conventional balloon angioplasty did not. Thus, placement of the Palmaz-Schatz stent provided a wider lumen than did conventional balloon angioplasty and, therefore, reduced the incidence of restenosis in chronic total coronary arterial occlusion. The lower restenosis rate of coronary stenting would be beneficial for long-term clinical outcome in patients with chronic total occlusion.

Asymptomatic occlusive lesions of carotid and intracranial arteries in Japanese patients with ischemic heart disease: evaluation by brain magnetic resonance angiography.

BACKGROUND AND PURPOSE: The purpose of this study was to elucidate the prevalence and degree of asymptomatic occlusive lesions in the carotid and intracranial arteries in Japanese patients with ischemic heart disease (IHD). METHODS: We performed carotid and intracranial MR angiography (MRA) on 67 patients (49 men, 18 women; age range, 40 to 78 years; mean age, 60.1 years) who had received selective coronary angiography for the clinical diagnosis of IHD. On the basis of these images, degree of stenosis in the regions of the bilateral carotid artery bifurcation and five regions of the intracranial arteries, ie, bilateral intracranial portions of the internal carotid arteries and the middle cerebral arteries and the basilar artery were estimated. RESULTS: Stenosis of more than 25% narrowing of the diameter of the target arteries was found in 15 patients (22.4%) in the extracranial carotid arteries and in 11 patients (16.4%) in the intracranial arteries. Most of the stenotic lesions were mild. The incidence of extracranial carotid stenosis and the severity of coronary atherosclerosis showed a significant correlation. The mean age of the patients with intracranial arterial lesions was statistically higher than those without intracranial lesions. CONCLUSIONS: Our data suggest that asymptomatic occlusive lesions in the carotid and intracranial arteries are fairly common in Japanese patients with IHD, although the degree of stenosis is relatively mild. Coexistence of carotid atherosclerosis should be suspected in IHD patients with severe coronary atherosclerosis, and the possibility of atherosclerosis in the intracranial arteries should be considered in aged IHD patients.

[Asymptomatic atheromatous cerebrovascular diseases in patients with acute myocardial infarction--evaluation by brain magnetic resonance angiography].

To investigate the relationship between atherosclerosis in the cerebral and coronary arteries, we examined the prevalence of asymptomatic atheromatous cerebrovascular lesions in patients with acute myocardial infarction (AMI). The subjects consisted of 33 consecutive AMI patients with angiographically proven coronary artery stenosis/occlusion(s) who had no history of ischemic strokes, and 33 age/sex matched controls without a history of coronary heart diseases or/and cerebrovascular diseases. Asymptomatic cerebrovascular lesions were evaluated by magnetic resonance angiography (MRA) with a 3-dimensional time-of-flight method within 2 months after the AMI onset. The evaluated arteries on MRA included the carotid bifurcation and the intracranial arteries (intracranial portion of the internal carotid artery, horizontal portion of the middle cerebral artery, and the basilar artery). Asymptomatic cerebrovascular stenotic lesions (more than 25% stenosis) on MRA were found in 8 AMI patients (24.2%) at the carotid artery bifurcation and 5 (15.2%) in the intracranial arteries, compared to 1 (3.0%) and 3 (9.1%) respectively in control subjects. The lesions in the carotid bifurcation were significantly frequent in the AMI patients (p < 0.05), while those in the intracranial arteries did not differ between the two groups. The AMI patients with the intracranial artery lesions were significantly older than those without such lesions (p < 0.05). The data obtained indicates that the coexistence of asymptomatic atheromatous cerebrovascular diseases, especially the lesions in the carotid bifurcation, should be considered in treating patients with AMI. The older AMI patients, who may have not only extracranial lesions but also intracranial lesions, should be treated more carefully.

Frequency analysis of QRS complex with bundle branch block in patients with and without sustained ventricular tachycardia.

To distinguish patients with bundle branch block (BBB) and sustained ventricular tachycardia (s-VT) from patients with BBB but without s-VT, a frequency analysis of the QRS complex was performed in 71 patients. Frequency analysis of the QRS complex of patients with left bundle branch block (LBBB) showed that patients with s-VT had significantly larger areas and area ratios between 50 and 100 Hz in the X lead than patients without s-VT (area: -0.905 +/- 0.231 vs -1.195 +/- 0.286. area ratio: -0.783 +/- 0.230 vs -1.125 +/- 0.310; P < 0.05). The area and area ratios from 100 to 200 Hz in the Z lead were also larger in patients with s-VT. The highest predictive accuracy using the area ratio from 50 to 100 Hz in the X lead was 86%, with a sensitivity and specificity of 83% and 88%, respectively. In cases with LBBB, time domain analysis showed no significant difference between patients with s-VT and those without s-VT. Frequency analysis of the QRS complex may be useful for distinguishing LBBB patients with s-VT from those without s-VT.

Prognostic significance of atrial fibrillation in dilated cardiomyopathy.

We evaluated the relation of atrial rhythm to a clinical course of treatment in 147 patients diagnosed with dilated cardiomyopathy (DCM). Thirty-six of the patients (24%) had either transient (9 patients) or persistent (27 patients) atrial fibrillation (AF). Compared with DCM patients with sinus rhythm (SR), the AF patients did not differ in age, left ventricular (LV) dimension, fractional shortening, or hemodynamic parameters, but the AF patients had slightly larger left atria. After a mean follow-up of 3.8 +/- 2.9 years, the NYHA functional classifications in the AF patients improved in 20 of the 36 (56%), whereas those of the SR patients improved in only 30 (27%) (p < 0.01). The actuarial 5-year survival rate was significantly better for AF patients than for SR patients (93% versus 68%, p < 0.05). LV function remained unchanged in SR patients but improved significantly in AF patients, particularly in patients with transient AF and with "rate-controlled" AF (those with a mean heart rate of less than 90 beats/min). This study suggests that atrial fibrillation may result in significant LV dysfunction, which is reversible in some cases once the arrhythmia is controlled. Aggressive antiarrhythmic therapy should be considered for patients initially diagnosed with dilated cardiomyopathy and atrial fibrillation.

Nonpharmacologic treatment of common atrial flutter guided by transient entrainment.

We attempted nonpharmacologic treatment for common atrial flutter in 7 patients, with direct current catheter ablation (CA) in 5 cases and cryoablation in 2 cases under the guidance of transient entrainment. Transient entrainment during common atrial flutter by pacing from the mid or low lateral right atrium (LLRA) revealed a long conduction time between the LLRA and the orifice of the coronary sinus (CSo) (73% to 121% of flutter cycle length). In 2 cases, fragmented electrograms were recorded at the low right atrial septum with durations of 150 msec and 155 msec, respectively. Because these fragmented electrograms were transiently entrained by rapid atrial pacing in the same manner as other atrial electrograms and were recorded in an area of long conduction, we believe that fragmented electrograms represent critical slow conduction. In 5 cases, CA was directed at this area. Three cases were successfully treated with 3 to 4 DC shocks of 100 J (follow up periods of 11.3, 4.5 and 3 months). Two cases which received 1 to 2 DC shocks of 100 J had recurrence of atrial flutter 6 and 4.7 months later, respectively. Two cases which showed atrial septal defect received surgical treatment. They were successfully treated with extended cryoablation in this same area (follow up periods of 26 and 9.2 months). In conclusion, extended ablation of an area of fragmented electrograms using transient entrainment may be an effective treatment for common atrial flutter.

Short- and mid-term follow-up results after percutaneous transvenous mitral commissurotomy.

This study reports the clinical follow-up for 6 months of 52 patients who underwent percutaneous transvenous mitral commissurotomy (PTMC). PTMC resulted in an increase in mitral valve area from 1.1 +/- 0.3 to 1.7 +/- 0.4 cm2 (p < 0.0001), a decrease in mean left atrial pressure from 16 +/- 7 to 13 +/- 5 mmHg (p < 0.0001), and an increase in exercise time from 4.6 +/- 2.1 to 6.3 +/- 2.3 min (p < 0.0001). At 6 months follow-up, mitral valve area was unchanged (1.7 +/- 0.4 cm2). Of 52 patients, 33 showed clinical improvement and 19 had no clinical improvement after PTMC. Univariate analysis showed (1) younger age, (2) echocardiographic score of 8 or less, (3) existence of mitral regurgitation of less than grade 2 after PTMC, and (4) amelioration in left atrial dimension, mean pulmonary artery pressure and exercise time after PTMC as correlative factors for clinical improvement. In conclusion, PTMC was an effective procedure for mitral stenosis, especially in younger patients with an echocardiographic score of 8 or less. Change in left atrial dimension was a good indicator of the effectiveness of PTMC.

Congestive heart failure in the elderly--echocardiographic insights.

One hundred and seventy-two patients (110 were greater than or equal to 65 years and 62 were less than 65 years) with congestive heart failure (CHF) were prospectively evaluated to determine various pathophysiologic mechanisms of CHF. The incidence of CHF with normal left ventricular (LV) systolic function was higher in elderly (30% vs 12%, p less than 0.05). Of the 110 elderly patients, LV systolic function was impaired in 77. Fifty-five patients had LV dilatation without increased wall thickness, and the clinical diagnosis was "dilated cardiomyopathy in the elderly". Twenty-two patients had hypertrophied LV and a high incidence of hypertension, and they were diagnosed as "hypertensive heart failure" due to contractile dysfunction. On the contrary, the remaining 33 patients did not have impaired LV contractile function. Thirteen patients lacking LV hypertrophy had enlarged atria. CHF was induced by reduced chamber compliance called "the stiff heart syndrome". Twenty patients had hypertrophied LV and a high incidence of hypertension. They were diagnosed as having "hypertensive hypertrophic cardiomyopathy of the elderly" and abnormalities of diastolic function accounted for the CHF. Since echocardiography can easily and accurately diagnose the pathophysiologic mechanism of CHF, an increased awareness of its occurrence in the elderly and use of echocardiography would reduce diagnostic and therapeutic errors.

[Clinical features of latent dilated cardiomyopathy].

To identify the evidence of presymptomatic manifestations of dilated cardiomyopathy (DCM), we studied 30 patients with latent DCM (mean 37 +/- 14 years) who satisfied the following criteria: 1) left ventricular (LV) systolic function was slightly reduced; 2) LV end-diastolic dimension (< 54 mm) and coronary arteries were normal. The incidence of ECG abnormalities was relatively high; nonspecific ST-T changes were the most common (90%). The incidence of grade 3 or 4 ventricular premature contractions according to Lown's classification on 24 hour ambulatory ECGs was 50%. Perfusion defects were observed in 83% on the thallium-201 images. Right ventricular biopsy showed that the interstitial fibrosis was milder (9 +/- 9%) in the study subjects than in 32 patients with DCM (17 +/- 8%) who were treated in our hospital, but there were no significant differences in the diameters of the myofibers (15 +/- 4 vs 17 +/- 4 microns) between the 2 groups. During the follow-up study, deterioration of LV dysfunction was observed in 3 patients. One patient died suddenly. These findings proved the importance of the early detection and characterization of latent state of DCM.

Rest-injected thallium-201 imaging for assessing viability of severe asynergic regions.

To evaluate the utility of rest-injected 201Tl initial and delayed images for assessing the viability of severe asynergic regions, we studied 17 patients with apparently prior infarcted myocardium in combination with 99mTc ventriculography before and after revascularization. In 51 regions with severe asynergy, the percent 201Tl uptake was calculated as the ratio of counts on the segment with asynergy to the maximum counts on the normal segment. Eleven of 14 regions with resting 201Tl redistribution (Group 1) had improved wall motion after revascularization. However, 14 of 37 regions without redistribution also improved (Group 2). Twenty-three regions without redistribution or improved wall motion after revascularization (Group 3) had lower regional 201Tl uptake on their delayed images than those in Groups 1 and 2. Moreover, the initial regional uptake of Group 2 was higher than that of Group 3. These results suggest that redistribution on rest-injected 201Tl scans indicates reversibility of severely asynergic myocardium and that high 201Tl uptake in regions without redistribution may predict improvement in wall motion after revascularization. We conclude that 201Tl uptake may be useful as a marker of viability of severe asynergic regions before revascularization.

[Pericardial effusion in acute myocardial infarction: clinical feature and significance].

To determine the incidence and clinical significance of pericardial effusion after acute myocardial infarction, two-dimensional echocardiography was serially performed in 137 consecutive patients. Pericardial effusion was observed in 45 patients (33%), of whom 22 were followed until they recovered and were discharged. Pericardial effusion was more frequent in patients with anterior acute infarction than those with inferior acute infarction, and so it was in non-recanalized patients than in recanalized ones. Patients with pericardial effusion had higher peak levels of creatine kinase, higher wall motion score indices, and higher defect scores of thallium imagings. The improvement of regional wall motion at an infarct zone in patients with pericardial effusion was less regardless of the successful early recanalization. These results show that pericardial effusion is a common event in patients with acute myocardial infarction and observation of transition of pericardial effusion is important for predicting prognosis.

[Progression from latent cardiomyopathy to dilated cardiomyopathy: a review of five cases].

We report 5 patients, who had no cardiac abnormalities at their initial evaluation but progressed to dilated cardiomyopathy (DCM) during a mean follow-up period of 8.2 years. Their echocardiograms revealed increases in left ventricular (LV) end-diastolic dimensions, deterioration of LV contractions, and reduction in the LV wall thickness. Electrocardiographic changes were developed of rhythm disturbances, intensified ST-segment and T-wave changes, and the prolonged QRS durations. These findings, especially those of electrocardiography, seemed to be important for an early detection and characterization of DCM.

Sympathetic nervous system response to dynamic exercise in complete AV block patients treated with AV synchronous pacing with fixed AV delay or with auto-AV delay.

To investigate the sympathetic nervous system (SNS) responses and circulatory responses to exercise in eight patients (five male and three female) with complete atrioventricular block (CAVB) treated with atrioventricular (AV) synchronous pacing, a symptom-limited, multistaged treadmill stress test was performed, and plasma norepinephrine (NE) and circulatory parameters were measured at rest, at peak exercise, and in the recovery period. The eight patients were tested using the fixed AV interval (150 or 156 msec). Their exercise tolerance was generally poor. In all measured points, plasma NE levels were significantly higher in the eight study patients than those in the 12 normal subjects (eight male and four female). Systolic blood pressure (SBP) of CAVB patients elevated significantly after exercise compared to that at peak exercise. Heart rate (HR) responses of CAVB patients were characterized by their poor increase at peak exercise. These results suggest that some latent cardiac dysfunction continues in the CAVB patients however satisfactorily the AV synchronous pacing might perform. AV synchronous pacing with three different kinds of auto-atrioventricular delay (auto-AVD) was applied to three of the eight patients. In each AVD mode, a treadmill stress test was performed repeatedly according to the same protocol. Plasma NE concentrations under the condition with fixed AVD at peak exercise increased compared to those under the other two conditions with auto-AVD. These findings suggest that AV synchronous pacing with auto-AVD was better than that with fixed AVD during exercise. Plasma NE response to exercise seems to be a useful indicator for evaluating the condition of patients treated with DDD pacemakers and their adaptation for cardiac function.

Restenosis after percutaneous transluminal coronary angioplasty--a histopathological study using autopsied hearts.

Restenosis was studied histopathologically by serial step sectioning of 22 coronary arteries from 21 patients in whom percutaneous transluminal coronary angioplasty (PTCA) had been performed (9 arteries from patients who had died shortly after PTCA and 13 from those who had died considerably later). Nine of the 13 arteries from the patients who had died long after PTCA were immunohistochemically stained using anti-actin antibody for examination of spindle-shaped cells proliferating in the intima. In the patients who had died shortly after PTCA, all 9 arteries showed fresh thrombus formation. In the patients who had died considerably later after PTCA, however, there was fragmentation of the internal elastic lamina (IEL) in 9 arteries. In each of these 9 arteries, a remarkable proliferation of intimal cells was observed on the intimal side, mainly at the site of the IEL fragmentation. These spindle-shaped cells were identified as smooth muscle cells (SMC) because they stained reddish-brown with Masson's trichrome, and because immunohistochemical staining with anti-actin antibody was also positive. In 2 arteries, proliferation of SMC and elastic fibers was observed on the luminal side of the intima, despite absence of fragmentation in the IEL. Proliferation of SMC in false lumens was identified in 2 patients with medial dissection. From the above findings, the following 4 forms of restenosis after PTCA have been identified: 1. thrombus formation; 2. proliferation of SMC on the intimal side, mainly around fragmentation in the IEL; 3. proliferation of SMC on the luminal side of the intima where there was no fragmentation of the IEL; and 4. proliferation of SMC in dissected false lumen. The proliferation of SMC on the intimal side of the disrupted IEL was thought to have been a result of migration of SMC from the media to the intima, because SMC proliferation was seen around the disrupted region.

Role of right ventricular asynergy and tricuspid regurgitation in hemodynamic alterations during acute inferior myocardial infarction.

To elucidate the role of right ventricular asynergy and tricuspid regurgitation (TR) in hemodynamic alterations occurring during right ventricular infarction, left and right ventriculography with pressure measurements were performed in 22 patients with acute inferior myocardial infarction. Twelve patients with a proximal right coronary artery (RCA) occlusion (Group I) had elevated right atrial pressure (16 +/- 4 vs 8 +/- 5 mmHg, p less than 0.01), low cardiac output (2.5 +/- 0.7 vs 3.5 +/- 0.6 l/min/m2, p less than 0.05) and a greater degree of TR, compared with 10 patients with a distal RCA occlusion (Group II). Inferoposterior wall asynergy of the right and left ventricles was similar in Groups I and II. In Group I, there was an additional asynergy of the anterolateral free wall of the right ventricle. Cardiac output in those patients was not related to the left ventricular ejection fraction (EF) but to the right ventricular EF. A greater degree of TR was found in association with a lower right ventricular EF. The decrease in cardiac output was closely related to the extent of TR. These results indicate that right ventricular asynergy and TR due to proximal RCA occlusion may play important roles as causes of hemodynamic alterations seen during the acute phase of inferior myocardial infarction.