[Recording quantitative myocardial perfusion parameters of high temporal and local resolution].
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Cardiac Catheterization↗
Biomedical subjects
R Erbel
Publications and source records attributed to R Erbel.
[Intraoperative diagnosis of the heart and great vessels--echocardiography].
Two-dimensional echocardiography including color Doppler techniques can be used for analysis of the morphology and function and of the blood flow of the heart and the great vessels. Epicardial echocardiography has the advantage of high resolution and multiple scan planes. The restriction to the intraoperative period is a clear disadvantage. In addition, the scan planes are difficult to standardize. Transesophageal echocardiography can be used for monitoring during the whole operative period but is restricted to horizontal and/or longitudinal scan planes. It is a non-contact procedure and thus, sterile conditions are not affected. For evaluation of surgical success, intraoperative echocardiography can be used for analysis in patients with congenital heart disease, mitral valve regurgitation, hypertrophic obstructive cardiomyopathy, and aortic dissection. Acute intraoperative revisions with a second extracorporal circulation period will avoid reoperation. In patients with coronary artery disease the flow within the bypass and also the status of the anastomosis can be scanned and may contribute to reduce the perioperative infarct rate. Intraoperative echocardiography needs additional costs and man power. Only after randomized comparative prospective studies have demonstrated that patients controlled by intraoperative echocardiography have a better outcome and prognosis than patients without intraoperative control this method will become routine in open-heart surgery.
Echocardiography↗
[Coronary vessel stent implantation in patients with symptomatic dissections following balloon dilatation].
Dissections after coronary balloon angioplasty are risk factors for acute or subacute vessel closure. Intracoronary stenting was developed to avoid this complication by wrapping the intimal and medial flaps against the vessel wall, which reduces the risk of acute thrombosis. A total of 17 stents were implanted into the coronary arteries of 10 patients with angiographically documented dissections after balloon angioplasty, who presented angina and ischemic ECG changes. Mean minimal stenosis diameter was 1.11 +/- 0.35 mm (65.1%) before, and 1.48 +/- 0.56 mm (53.9%, n.s.) and 2.45 +/- 0.62 mm (23.5%, p less than 0.005), respectively, after balloon angioplasty with and without taking the dissection membrane into account. All patients reported an immediate recovery of their anginal complaints after stent delivery, and ischemic ECG changes disappeared. The mean residual stenosis after coronary stenting was measured as 3.33 +/- 0.23 mm (0%, p less than 0.001). The immediate control angiograms and these after 24 h depicted smooth vessel walls without any irregulations at the site of implantation, and the mean residual stenosis diameter remained unchanged after 24 h (3.3 +/- 0.23 mm; 1.2%, p less than 0.001). No patient suffered acute myocardial infarction, one patient underwent coronary bypass surgery because of persisting episodes of angina pectoris. Thus, intracoronary stenting seems to be a secure and effective method to handle dissections after balloon angioplasty, and perhaps reduces the rate of acute complications and the need for emergency bypass surgery after coronary balloon angioplasty.
Aged↗
New mechanical devices for treatment of coronary artery disease.
Percutaneous high-speed coronary rotablation allows to remove arterio-sclerotic material from the vessel wall. A diamond-coated (15-30 microns) brass burr drill fastened to a flexible drive shaft rotating and tracking along a drill coaxial guide wire is used. The turbine rotates the drive shaft at 150,000-190,000 rpm. High-frequency rotational angioplasty was successful in 27 of 28 patients, but in about 34% additional PTCA was necessary. Only one patient went to bypass surgery, and myocardial infarction (CK less than 150 u/l) occurred in only one of 28 patients. No vessel perforation was observed. All vessels were open at 24 h control. The restenosis rate was not increased. The main indication for high-speed rotational angioplasty seems to be rigid sclerotic lesions that cannot be passed by a conventional balloon catheter. Whether restenosis rate can be reduced by this method will be judged in future studies. In order to avoid acute complications of PTCA and to reduce restenosis rate, coronary stents were developed. Self-expandable and balloon-expandable stents are available. It could be demonstrated that these stents can be used as a bail-out system and can block elastic recoil of coronary arteries. The major remaining problem is that of subacute closure of coronary vessels. In order to prevent this, treatment with coumarine, acetylsalicylic acid, and dipyridamol is necessary. Coronary stents can be successfully delivered in more than 90% of the patients, as demonstrated by a cooperative study. In a highly selective patient group using single stents, restenosis rate measured 15%, but was higher in patients with multiple stents.
Angioplasty, Balloon, Coronary↗
[Acute and chronic effects of molsidomine in therapeutic coronary angioplasty].
The effects of the molsidomine metabolite SIN-I (0.5 mg) on tolerance to ischemia were studied in twelve patients during coronary angioplasty of the LAD. SIN-I resulted in a significant prolongation of time to ST-segment alteration one, five and ten minutes after intracoronary injection. Beside hemodynamic reasons the effects of SIN-I on circulating blood cells and collateral perfusion are discussed as mechanisms of action. The effects of molsidomine (2 X 8 mg/d) on restenosis rate after initially successful coronary angioplasty were studied in 393 patients in a prospective, randomized and controlled trial. 29% of patients treated with molsidomine experienced restenosis at control coronary angiography at six months. The control group receiving nifedipine (3 X 20 mg/d) and acetylsalicylic acid (1 X 500 mg/d) showed a restenosis in 33% of patients. Therefore, molsidomine seems as effective as nifedipine and acetylsalicylic acid in treating patients after coronary angioplasty.
Angioplasty, Balloon, Coronary↗
[Hemodynamics after sublingual administration of captopril in severe heart failure. A pilot study].
In a preliminary trial, 23 patients in severe left-heart failure and, in some instances, also right-heart failure (NYHA classes III and IV) received a single sublingual dose of 25 mg captopril. Invasive measurement of various haemodynamic parameters indicated (1) an increase in cardiac index and stroke-volume index of 34% and 38%, respectively (P less than 0.001 for each); (2) decrease in pulmonary artery and systemic pressures by an average of 7% and 11.4% (P less than 0.01 and less than 0.001, respectively); (3) no significant change in heart rate and mean right atrial pressure; (4) decrease in systemic and pulmonary artery resistance by 33% and 29% (P less than 0.001 for both); (5) an increase in left ventricular stroke work index by 18% (P less than 0.001); and (6) a fall in heart rate x pressure product by 10% (P less than 0.005). These haemodynamic changes started within 12 to 23 minutes after captopril administration, the peak effect occurring between 40 and 90 minutes. Baseline values were reached after three hours. Reproducibility measurements revealed a close quantitative and temporal correlation (r for all greater than 0.8). To obtain similar changes of cardiac function 1.65 micrograms/min.kg sodium nitroprusside were needed. The results indicate that sublingual administration of captopril in severe heart failure will achieve early and significant improvement in cardiac function.
Administration, Sublingual↗
[Balloon dilatation and coronary vascular stent implantation].
To avoid acute complications and restenosis after percutaneous transluminal coronary angioplasty coronary stents were developed. For the first time in 2 patients with severe lesions of the left anterior descending coronary artery 3 Palmaz-Schatz stents were implanted after application and fixation by balloon inflation. The vessels showed larger diameters with smoother surface and smaller gradients compared to balloon angioplasty as related to a blockade of the elastic properties of the vessel and suggested fixation of intima or media dissection. The implantation of the coronary stents was without complications. The control after 24 hours showed an open vessel with unchanged diameter. The patients were without symptoms during control after 4 weeks. Based on this and previous work the implantation of coronary stents seems to open a new dimension for percutaneous transluminal coronary angioplasty because vessel occlusions are prevented and restenosis possibly reduced. The newly designed stents show elementary constructive alternatives to currently used types.
Angioplasty, Balloon↗
[Mitral valve prolapse syndrome].
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Adolescent↗
Cardiac arrhythmias and heart rate in hyperthyroidism.
The arrhythmia profile and heart rate (HR) were analyzed by 24-hour Holter monitoring in 37 hyperthyroid patients before (triiodothyronine [T3] hormone level = 331 +/- 108 ng/dl), during (T3 level = 202 +/- 98 ng/dl) and after an antihyperthyroid therapy of 8 to 89 weeks' duration (T3 level = 149 +/- 41 ng/dl). The data were compared with those of 50 control subjects free from cardiac disease. Only 12 hyperthyroid patients (32%) had complex ventricular arrhythmias (Lown grade 3 or 4) as compared with 6 normal subjects (12%, p greater than 0.05). Three patients (8%) had repetitive ventricular arrhythmias (Lown grade 4A/B) as compared with 4 normal subjects (8%, p greater than 0.05). Supraventricular premature complexes occurred more often in hyperthyroid patients than in normal subjects before and after therapy (p less than 0.001). The prevalence of supraventricular tachycardia decreased from 8 patients to 1 during therapy (p less than 0.002). The HR decreased from 95 +/- 13 to 79 +/- 9 beats/min after therapy, but was still increased as compared with the normal subjects (72 +/- 8 beats/min, p less than 0.001). A day/night difference in HR greater than 10% was found in 32 patients (86%) and was more pronounced than in the normal group (p less than 0.001). Compared with the normal HR profile, the HR curve of hyperthyroid patients was shifted to a higher level (about 20 beats/min). Serum T3 level correlated best with HR at night in hyperthyroid patients (r = 0.74, p less than 0.001). Thus, hyperthyroid patients show frequent supraventricular arrhythmias that might be reversible during therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
Arrhythmias, Cardiac↗
[High-frequency rotational atherectomy in coronary heart disease].
Percutaneous high frequency coronary rotational ablation (PTCR) was used in 10 patients with significant coronary artery disease. PTCR removes arteriosclerotic material from the vessel wall. A diamond-coated (60-80 micron) brass burr-drill, fastened to a flexible drive shaft rotating and tracking along a central coaxial guide wire, was used. The turbine rotates the drive shaft in excess of 150,000-190,000 revolutions per minute. PTCR was successful in all patients, but in three additional percutaneous transluminal coronary angioplasty (PTCA) was then successfully performed. Coronary dissection occurred only once, requiring surgery which was successful. No vessel perforation was observed. All vessels were open on the coronary angiograms performed after 24 hours. The main indication for PTCR seems to be a rigid and longer lesion which can not be dilated with the balloon catheter.
Angioplasty, Balloon↗
Echocardiography in diagnosis of aortic dissection.
In a multicentre study the accuracy of echocardiography was measured in 164 consecutive patients with suspected aortic dissection. The diagnosis was subsequently proven (82 patients) on the basis of transthoracic and transoesophageal echocardiography and additional diagnostic procedures, including computed tomography (CT), aortic angiography, and surgery and/or necropsy. The sensitivity and specificity of echocardiography were 99% and 98%, respectively, with positive and negative predictive values of 98% and 99%. For CT sensitivity was 83%, specificity 100%, and positive and negative predictive values 100% and 86%, respectively. For aortography sensitivity and specificity were 88% and 94%, and the positive and negative predictive values 96% and 84%, respectively. Echocardiography, including the transoesophageal route, can provide accurate diagnosis of aortic dissection within 15 min. Diagnostic difficulties occur only in a few type II dissections, when complementary diagnostic procedures, including CT or angiography, may be needed. To clarify branch involvement angiography is required.
Acute Disease↗
High-frequency rotablation of occluded coronary artery during heart catheterization.
High-frequency rotation atherectomy of an occluded left circumflex coronary artery was performed in a 45-year-old man. Over a 0.009 inch flexible tip steel wire a diamond-coated brass burr fastened to a flexible drive shaft that rotates and tracks was advanced. The drive shaft was connected to a turbine and driven by compressed air with 150,000 rpm. After rotablation of the posterior lateral branch over 3 cm with a 1.5 mm burr and rotablation with a 1.75 mm burr of the posterior branch of the left circumflex coronary artery the vessel was reopened with a smooth surface without perforation and dissection. 24 h control and 6 mo control revealed an open coronary vessel. High frequency rotating coronary angioplasty seems to be a promising alternative method to PTCA in opening totally occluded coronary arteries.
Angioplasty, Balloon↗
Semiquantitative grading of mitral regurgitation by color-coded Doppler echocardiography.
We evaluated patients with mitral regurgitation by color-coded Doppler echocardiography using a semiquantitative score system, which is useful in the clinical setting, by providing rapid discrimination between mild, moderate and severe regurgitation. The study was performed in 42 patients (19 female, 23 male) mean age 58 years, range 23-75 years with mitral regurgitation of different etiology. Color-coded Doppler measurements were compared to angiographic findings using a three point score system. In addition to such parameters as maximal jet length, area and the ratio jet area/left atrial area, we also considered the duration of regurgitant flow. The best correlation was obtained for the maximal area of the jet multiplied by the duration of regurgitant flow/cycle length (r = 0.88), determined in the apical plane where the jet was best visualized. For the parameter area of jet alone, the correlation coefficient was 0.81, for the length of the jet the value was r = 0.65 and comparison of the areas of jet and left atrium gave a coefficient of 0.77. A clear separation between mild and severe regurgitation was observed only for the parameter calculated by multiplying the area of the jet by the duration of mitral regurgitation. In only 7% of the patients with moderate and severe regurgitation could we observe an overlap. This parameter, therefore, represents a useful method for estimating in a semiquantitative manner the severity of mitral regurgitation by color-coded Doppler echocardiography.
Adult↗
Flow patterns of mitral regurgitation due to different etiologies: analysis by color-coded Doppler echocardiography.
We have used cross-sectional real time color-coded Doppler echocardiography to characterize the patterns of the regurgitant jet seen in mitral valvar disease of different etiologies. We studied 118 patients with mitral regurgitation due to rheumatic valve disease (n = 26), hypertrophic obstructive cardiomyopathy (n = 22), dilated cardiomyopathy (n = 35) and prolapse of the leaflets of the mitral valve (n = 35). We analyzed the origin, spatial distribution, extent and duration of the regurgitant jet. A semiquantitative grading system was used to evaluate the extent of the jet by measuring its maximal area and the duration of regurgitant flow. Typical flow patterns could be observed in hypertrophic obstructive cardiomyopathy, (in which the crescent shaped jet was elongated in midsystole and directed posteriorly) in dilated cardiomyopathy (in which oval shaped jets were observed throughout systole) and in prolapse of the leaflets (in which early or late systolic regurgitant jets occurred with an eccentric "drop-like" pattern, being directed posteriorly in patients with a prolapse of the aortic leaflet and anteriorly in those with a prolapse of the mural leaflet of the valve). A large variety of patterns was found in rheumatic disease due to the individual deformation of the leaflets. A comparison of the measured area of the jet revealed no significant differences between regurgitation caused by rheumatic valve disease and dilated cardiomyopathy. The regurgitation in 80% of these patients was of moderate to severe degree. In contrast, regurgitation due to prolapse of the leaflets or hypertrophic obstructive cardiomyopathy appeared to be of mild to moderate degree in 90% of cases.
Adult↗
Long-term results of thrombolytic therapy with and without percutaneous transluminal coronary angioplasty.
The effects of combined intravenous and intracoronary streptokinase without (Group I, n = 103) or with (Group II, n = 103) immediate coronary angioplasty were evaluated during a long-term (3 year) follow-up of 206 patients with acute transmural myocardial infarction. There were no baseline differences between the groups with regard to gender, age, infarct location, serum creatine kinase levels, time between onset of symptoms and treatment and coronary artery patency rate. Angioplasty was performed with a success rate of 69% and a reocclusion rate of 2%. Elective angioplasty was performed in 22 (21%) of 103 patients in Group I and 9 (9%) of 103 patients in Group II, with a success rate of 86% and 100%, respectively, reflecting the higher incidence of angina pectoris and antianginal therapy in Group I. Coronary bypass surgery was performed in 21 (20%) of 103 patients in Group I and 20 (19%) of 103 patients in Group II; there was one operative death in each group. During follow-up, coronary reocclusion or reinfarction, or both, occurred in 25 (29%) of 87 patients in Group I and in 16 (18%) of 87 patients in Group II with reperfused vessels (p = NS). Heart failure occurred in 40% of the patients in both groups who had increased end-diastolic and end-systolic volumes. The survival rate after 3 years was 78% in Group I and 80% in Group II (p = NS). Thus, long-term follow-up of patients with acute transmural infarction treated with and without immediate angioplasty does not demonstrate any difference with regard to clinical outcome and mortality.
Angioplasty, Balloon↗
Influence of incremental preoperative risk factors on the perioperative outcome of patients undergoing emergency versus urgent coronary artery bypass grafting.
A retrospective analysis of 127 patients with impending myocardial infarction undergoing coronary artery bypass grafting was performed to evaluate incremental risk factors associated with perioperative mortality and morbidity. Fifty-four patients (group 1) were operated upon as emergencies within 24 h and 73 patients underwent urgent coronary revascularization within a mean of 3.4 days (group II) after admission. The incidence of non-transmural myocardial infarctions (NTMI), haemodynamic parameters, the number of diseased vessels and the incidence of a preceding percutaneous coronary dilatation (PTCA) were not statistically different between the groups. The overall perioperative mortality was 8.7% (16.7% group I, 2.7% group II). Major non-fatal complications were frequent in the surviving collective including low cardiac output in 14 patients (12.1%) and transmural or subendocardial perioperative infarction in 12 patients (10.3%). Perioperative mortality was associated with reduced left ventricular myocardial function (P less than 0.001), operation within 24 hr after onset of anginal symptoms (P less than 0.001) or subendocardial infarction (P less than 0.025) in the 4 weeks before operation. Perioperative mortality was independent of the degree of coronary stenosis, number of distal anastomoses or performance of a coronary endarterectomy. Of the patients, 90.5% (87.5% of group I and 92.3% of group II) included in a mean follow-up of 16.8 months (range 5-27 months) were graded into Canadian Heart Functional Class I. Successful coronary surgery for acute myocardial ischaemia results in excellent late functional recovery. The major risk factors for fatal perioperative outcome are reduced left ventricular function and the necessity of every early surgical intervention.
Angioplasty, Balloon, Coronary↗
Emergency surgical revascularization following coronary angioplasty: evaluation of operative results by isoenzyme analysis and electrocardiography.
Seventeen patients underwent emergency coronary artery bypass grafting due to balloon catheter induced occlusion or dissection of a major coronary artery. Patients were revascularized within a maximum of 210 min from the onset of ischaemia and received an average of 1.6 distal anastomoses. A perioperative transmural or non-transmural myocardial infarction as diagnosed by CK-MB activity and electrocardiographic patterns occurred in 7 patients (41.2%). One early death resulted in an overall perioperative mortality of 5.9%. Successful preservation of myocardium was demonstrated in 10 patients by a rapid decline of CK-MB activity, no perioperative electrocardiographic changes and no requirement for inotropic support. The incidence of a perioperative myocardial infarction was independent of the anginal status before coronary angioplasty or the angiographic evidence of a complete occlusion versus a dissection. Major ischaemic myocardial complications associated with coronary angioplasty are rare but frequently catastrophic events. Fast surgical intervention is mandatory to prevent myocardial infarction or to limit the extent of injury. The operative outcome can be evaluated by careful analysis of time release curves and cumulative parameters of CK-MB activity.
Adult↗
Unorthodox diagnostic procedure in a rare case of intrapericardial malignant schwannoma.
To establish preoperatively the cytology of a large right atrial tumour, an echoguided transcutaneous thin needle aspiration using a transhepatic approach was performed. Cytology suggested myxoma, which had been mimicked by regressive changes within the tumour, while the histologic examination of the removed specimen revealed a malignant pericardial Schwannoma. In spite of this discrepancy we think that solid tumours located at the free atrial wall are accessible to ultrasound guided puncture without great risk.
Adult↗