Electrophysiologic testing after aortic valve replacement in two patients with aortic stenosis and preoperative ventricular fibrillation.

In two patients with severe aortic stenosis successful resuscitation from ventricular fibrillation was documented by Holter recording/ECG monitoring. After aortic valve replacement programmed ventricular stimulation was performed in both patients, but ventricular tachycardia/ventricular fibrillation was not inducible. The patients were left without antiarrhythmic therapy and have been free from cardiac events for 18 and 20 months, respectively. The prognostic value of postoperative electrophysiologic testing after aortic valve replacement in patients with severe aortic stenosis and preoperative resuscitation is discussed.

[The effect of concomitant aortic valve insufficiency on the values of Doppler sonographic gradient determination in patients with aortic stenosis]. / Einfluss der begleitenden Aorteninsuffizienz auf das Ergebnis der dopplersonographischen Gradientenbestimmung bei Patienten mit Aortenstenose.

We examined the influence of concomitant significant aortic incompetence (AI) on Doppler-gradient measurements in valvular aortic stenosis (AS) by comparing catheter and Doppler gradients of 51 patients with isolated AS and of 24 patients with additional AI. In patients with additional AI there was a significantly greater overestimation of the peak-to-peak gradient by the maximal instantaneous Doppler gradient (AS + AI: overestimation 31.0 +/- 17.6 mm Hg, AS: overestimation 10.5 +/- 20.2 mm Hg; p less than 0.01) and also by the maximal instantaneous catheter gradient (AS + AI: overestimation 32.8 +/- 11.8 mm Hg, AS: overestimation 20.4 +/- 14.0 mm Hg; p less than 0.01). Comparison of the respective catheter-derived and Doppler-sonographically measured instantaneous and mean gradients showed no differences between the two patient subgroups. Higher instantaneous gradients in patients with additional AI are mainly explained by the lower end-diastolic aortic pressure. However, Doppler-sonographic overestimation of the severity of stenosis in patients with combined AS + AI, due to the sole measurement of the instantaneous gradient in clinical practice, should be of limited importance because in these patients significant AI already sufficiently indicates aortic valve replacement.

Day to day reproducibility of Doppler sonographic measurements in patients with valvular aortic stenosis.

High reproducibility of Doppler gradient measurements is necessary for both the reliable noninvasive assessment of the severity of aortic stenosis and for repeated follow-up examinations in individual patients. We therefore studied day to day reproducibility of Doppler sonographically measured peak pressure drops in 46 patients with valvular aortic stenosis. Clinically stable patients were examined twice within 29 +/- 18.2 days by the same examiner. Peak pressure drop (PPD) and peak flow velocity differed between the two examinations by 8.6 +/- 7.0 (range 0-29) mmHg and by 0.25 +/- 0.18 (range 0-0.7) m/s, respectively. Reproducibility was comparable in patients with excellent, good, and moderate quality examinations, but was lower in the 6 patients with poor quality examination. Variability of PPD, but not of peak flow velocity was higher (p less than 0.05) in patients with severe (PPD greater than 60 mmHg) stenosis. Reproducibility was comparable in patients with or without concomitant aortic incompetence and in patients with normal or reduced left ventricular function. Similar reproducibility was obtained in patients with heart rate changes below or above 10 beats/min between the two examinations. It is concluded that good reproducibility of Doppler measurements in patients with aortic stenosis allows reliable noninvasive assessment of the severity of the stenosis. In follow-up studies of patients with mild to moderate aortic stenosis increases in peak flow velocity in excess of 15% (mean day to day variability +2 SD) are highly indicative of the true progress of the stenosis.

[Electrophysiologic study in patients with syncope of unknown cause]. / Elektrophysiologische Untersuchung bei Patienten mit unklaren Synkopen.

Electrophysiologic studies were performed in 51 patients with syncopes of unexplained origin. 25 patients (49%) had organic heart disease. Electrophysiologic testing included determination of corrected sinus node recovery time, AV-nodal effective refractory period, AH- and HV-intervals, and AV-nodal Wenckebach rate. During programmed right ventricular stimulation, 1-3 premature stimuli were used. 26 patients (53%) had an abnormal outcome that strongly suggested an arrhythmogenic cause of the reported syncopes. In ten patients (20%), corrected sinus node recovery time was prolonged; AV-nodal conduction disturbance was manifest in two patients (4%); reversibility with atropine was shown in one patient. Six patients (12%) had an infrahisian conduction delay with an HV-interval longer than 70 ms. Eight patients (15.6%) had either symptomatic ventricular tachycardias (n = 4), AV-nodal reentry tachycardias (n = 2), or inducible symptomatic rapid atrial fibrillation (n = 2). In one additional patient, ventricular tachycardias could not be reinitiated after ending tricyclic antidepressant drug medication. The diagnostic yield of the electrophysiologic study was not influenced by the presence of organic heart disease. Patients with prolonged corrected sinus node recovery time, prolonged HV-interval, and irreversible AV-conduction delay underwent pacemaker implantation (n = 17). Patients with rapid response to programmed stimulation received antiarrhythmic medication, the efficacy of which was assessed by serial electrophysiologic testing until non-inducibility was obtained. The mean follow-up period was 11 months (1-31 months). Overall 2-year mortality was 17%. In 4/5 patients, death was unrelated to the cause of syncope.(ABSTRACT TRUNCATED AT 250 WORDS)

[Doppler echocardiographic determination of aortic valve gradients]. / Doppler-Echokardiographische Bestimmung des Aortenklappengradienten.

Doppler-echocardiography is the most important non invasive method for the assessment of the severity of aortic stenosis. After measuring the maximal transstenotic flow velocity (= Vmax) the maximal pressure drop between left ventricle and aorta (= maximal instantaneous gradient) can bei calculated according to a simple formula. The accurate determination of Vmax may be difficult and time consuming, however, and when interpreting the Doppler-data it is important to realize that there is always a systematic numerical difference between the instantaneous gradient and those gradients which one usually measures at catheterization (peak to peak and mean gradient respectively). In mixed aortic valve disease the aortic insufficiency will distort the relationship between the various gradients still further. Despite these problems Doppler-echocardiography is extraordinarily useful in quantitating aortic stenosis and obviates the need for catheterization in most patients.

[Sudden cardiac death during long-term ECG monitoring of a patient with aortic stenosis]. / Plötzlicher Herztod im Langzeit-EKG bei einem Patienten mit Aortenstenose.

Sudden cardiac death was documented on a Holter-monitor ECG in a 71-year-old man with known, but unoperated, calcific aortic stenosis (peak transvalvar gradient of 90 mm Hg). The tracing showed the development of a, presumably stress-induced, sinus tachycardia with broad QRSs and rapid transition to ventricular fibrillation. This rarely documented example of cardiac death in a patient with aortic stenosis during long-term ECG monitoring is of special interest because the patient had neither an inverse therapy effect nor impaired left-ventricular function.

Reproducibility of myocardial thallium-201 washout in studies applying a standardized dipyridamole stress protocol.

Thallium-201 (201Tl) washout analysis was proposed as an adjunctive tool to improve the detection of coronary artery disease (CAD). Since reproducibility of 201Tl washout in dipyridamole (DPM) stress studies is unknown, this item was evaluated in 32 patients (24 with CAD, 8 without CAD), who were scintigraphed twice within 1-2 weeks. At 2 minutes following DPM infusion (0.5 mg/kg/5 min), 2 mCi 201Tl were injected. Global and segmental washout were calculated by comparing circumferential profiles of respective background-corrected stress (left anterior oblique (LAO) 45 degrees: 8 min postinfusion (p.i.), 35 min p.i.; anterior (ANT): 17 min p.i.; LAO 70 degrees: 26 min p.i.) and redistribution (4 h p.i.) images. Whereas visual findings were comparable for study I and II, reproducibility of 201Tl washout was low, indicated by comparing variances among patients with variance between studies, which were 28.8 and 71.2% of total variance, respectively. Mean differences of segmental washout between the studies ranged from 9.75 to 19.24% with only minor differences with regard to the different views and segments evaluated. Variability was lower using the intermediate instead of the initial scintigram as reference for the redistribution image (12.87 +/- 11.64% vs. 18.59 +/- 14.43%, n = 85; p less than 0.01). Variability was higher for nonstenosed compared to stenosed segments (14.54 +/- 11.41%, n = 32 vs. 9.89 +/- 8.03%, n = 28, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

[Doppler sonography quantification of mitral valve stenosis in patients with and without mitral valve insufficiency]. / Doppler-sonographische Quantifizierung der Mitralstenose bei Patienten mit und ohne Mitralinsuffizienz.

Fifty-three patients with mitral stenosis (MS) were examined by two dimensional (2DE) and Doppler echocardiography (Dop). Twenty-nine of them also had mitral insufficiency (MI) as judged by Dop. The mitral valve area (MVA) was calculated from Doppler using the "pressure half time" and was compared with MVA by 2 DE. There was a good correlation between both methods in all 53 patients (r = 0.88; SEE = 0.34 cm2) but also in the subgroups with pure MS (r = 0.86; SEE = 0.29 cm2) and MS + MI respectively (r = 0.90; SEE = 0.38 cm2). The accuracy and the reproducibility of the Doppler method was highly dependent on the severity of the stenosis. In 19 cases with mild MS (MVA by 2 DE greater than 1.5 cm2) the absolute difference between MVA 2 DE and Dop averaged 0.39 cm2. The difference between the maximal and minimal Doppler MVA which reflects the variability of this method averaged 0.65 cm2 in this group. In cases with significant MS (MVA by 2 DE less than or equal to 1.5 cm2) the average difference 2 DE -Dop and Dop max-Dop min was only 0.20 cm2 and 0.27 cm2 respectively. In patients with comparable degrees of stenosis additional MI did not adversely affect the accuracy of the Doppler method. We conclude that Doppler echo allows an accurate quantitation of mitral stenosis even in patients with associated MI.

Structurally modified fatty acids: clinical potential as tracers of metabolism.

Recently 15-p-iodophenyl-beta-methyl-pentadecanoic acid (BMPPA) was proposed for use in myocardial scintigraphy, as a possible probe of metabolic processes other than beta-oxidation. In 19 patients (CAD/15, St.p. Mi/7; control 4) myocardial scintigraphy was carried out after i.v. I-123-BMPPA (2-4 mCi). Data were collected (LAO 45 degrees/14; anterior/5) for 100 min in the fasted patients. Organ to background (BG) ratios were calculated for the heart (H) and liver (L), and the elimination (E) behaviour was analyzed from BG (vena cava region) corrected time activity curves. In 10 patients plasma and urine were examined. By CHCl3/MeOH extraction of plasma samples (90 min after injection), both in water and in organic medium soluble catabolites were found. TLC fractionation showed that those were co-migrating, compared to standards, with bencoic acid, BMPPA and triglycerides. In the urine (0-2 h after injection, 4.1% dose) hippuric acid was found. The mean t-max of BMPPA occurred at 15 min in the heart and at 9 min in the liver (P less than 0.01), with H/BG and L/BG ratios of 1.8 and 2.1, respectively. The elimination of BMPPA was slower from the heart than from the liver (P less than 0.01). It was biexponential from the liver in all cases (means: t/2 I, 11.4 min; t/2 II, 92 min; t/2 I uncor., 38 min) with the size of phase I smaller than that of phase II (means: I/II, 0.57). From the heart BMPPA turnover was biexponential in 11 patients (means: t/2 I, 13.8 min; t/2 II, 187 min; t/2 I uncor., 65 min; I/II, 0.34), but monoexponential in 8 (means: t/2, 218 min).(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of thallium-201 imaging on clinical assessment and management of patients with chest pain.

The histories, rest, and exercise ECG results of 60 patients without myocardial infarction complaining of chest pain were submitted to 6 physicians (3 cardiologists and 3 noncardiologists) who were unaware of the angiographic findings. The physicians were requested to estimate the probability of coronary artery disease present in percentages and to assess the need for coronary angiography on a five-point scale (1 = definitely not indicated, 5 = definitely indicated). After obtaining the results of thallium-201 imaging following dipyridamole (0.50 mg/kg intravenously) administration, the physicians were again requested to estimate probability and need for angiography. In the 43 patients with coronary artery disease the judgment of probability was increased significantly after 201Tl from 75.6 +/- 20.2% to 82.9 +/- 23.2% (p less than 0.001) and the need for angiography from 4.3 +/- 0.9% to 4.5 +/- 0.9% (p less than 0.001). In the subgroup of patients with atypical angina the relative change in probability was higher than in other subgroups of patients with coronary artery disease. In the 17 patients with normal coronary arteries the probability estimation fell after 201Tl from 36.7 +/- 22.0% to 24.8 +/- 21.0% (p less than 0.001), the need for angiography was decreased from 2.7 +/- 1.1% to 2.2 +/- 1.2% (p less than 0.001). With the 201Tl information, cardiologists performed a better diagnostic differentiation of patients with and without coronary artery disease than noncardiologists. The study demonstrates the improvement of clinical diagnosis in patients with chest pain by thallium-201 imaging and confirms the favorable influence of the method on the management of the patients in terms of indications for coronary angiography.

[Changes in the left ventricular ejection fraction during exercise and in the thallium-201 perfusion after administration of dipyridamole in patients with coronary disease]. / Anderungen der linksventrikulären Auswurffraktion unter Belastung und der Thallium-201-Perfusion nach Dipyridamol bei Koronarpatienten.

46 patients with coronary artery disease (at least 70% stenoses) were studied with thallium-201 imaging following dipyridamole (0.50 mg/kg bodyweight intravenously) with 4-hour control and by radionuclide ventriculography at rest and during symptom-limited bicycle exercise in supine position. 38 patients (83%) had positive thallium-201 findings with persistent defects in 18 and transient defects in 20 cases. Mean left ventricular ejection fraction (EF) fell during exercise from 56.1% +/- 13.3 to 50.2% +/- 14.5 (p less than 0.001). 43 patients (93%) showed an abnormal EF response to exercise (rise of less than 10% of the control EF during exercise). In 8 patients with false negative thallium-findings the EF did not change from rest to exercise (64.1% +/- 10.0 vs. 64.6% +/- 8.5), however, in the 20 patients with transient Tl-201 defects a significant fall of the EF was noted (60.8% +/- 9.1 vs. 49.8% +/- 10.9, p less than 0.001), in the 18 patients with persistent defects only a slight decrease of the EF was induced with exercise (47.3% +/- 14.0 vs. 44.2% +/- 16.1, p less than 0.02). Thus transient Tl-201 defects usually predict functional impairment of the left ventricle with exercise, persistent defects suggest impaired rest function with only minor further dysfunction during exercise. Compared with rest and exercise ECG in these patients, both radionuclide techniques showed a significantly higher sensitivity.

[Reproducibility of repeated measurements using M-mode echocardiography, radionuclide ventriculoradiography and systolic time intervals]. / Reproduzierbarkeit von Wiederholungsmessungen mit M-Mode-Echokardiographie, Herzbinnenraumszintigraphie und systolischen Zeitintervallen.

The reproducibility of M-mode echocardiography, radionuclide ventriculography, and systolic time intervals (PEP/LVET) was studied in 16 patients with symmetrically contracting left ventricles and no signs of coronary heart disease. The values were determined four times in these 16 patients: twice each on day 1 and day 8 at an interval of 2-3 h. The mean EF and PEP/LVET values were nearly identical in all 4 repeat studies. There was a high correlation of echocardiographic and scintigraphic EF measurements (r between 0.90 and 0.96); the correlation between PEP/LVET and EF was considerably poorer (r ranging from -0.56 to -0.79). There was no difference in mean serial variabilities of EF for all repeated studies performed on the same day and on separate days for either echocardiography or radionuclide ventriculography. The mean variability of absolute EF for repeated studies was 2.9 +/- 2.4% for M-mode echocardiography and 3.4 +/- 2.4% for radionuclide ventriculography. To be attributed to nonrandom physiological alterations the absolute change in EF in an individual patient should be at least 8% for echocardiography and 9% for radionuclide ventriculography. The mean variabilities of PEP/LVET were different in studies performed on the same day and on separate days (0.03 +/- 0.02 vs 0.04 +/- 0.03, p less than 0.01). In 7 further patients the effect of dobutamine infusion was studied.(ABSTRACT TRUNCATED AT 250 WORDS)

The use of 123I-labeled heptadecanoic acid (HDA) as metabolic tracer: preliminary report.

The feasibility of using 123I-heptadecanoic acid (HDA) as a metabolic tracer was studied. Different administration routes of HDA were compared. An intracoronary bolus injection was given to calves (n = 3), and an intravenous injection was given to patients (n = 4). In addition, we examined the influence of 4-h halothane anesthesia in calves and in patients the impact of an insulin (1.5 IU/kg) + glucose (1.5 g/kg) infusion on the myocardial kinetics of HDA. Data were accumulated with a scintillation probe in calves (t = 50 min) and a gamma camera in patients (t = 70 min). In calves after an intracoronary bolus injection of HDA the myocardial time-activity curve could be described by two exponentials. The mean elimination half-time of the initial phase (ta 1/2) was 7.3 min and that of the second phase (tb 1/2) was 35 min. The ratio of the size of the initial and second component at to was 0.93. Halothane anesthesia prolonged the elimination half-times and reduced the component ratio. The biphasic behavior of the myocardial time-activity curve was maintained in patients after intravenous administration of HDA under basal conditions (initial ta 1/2 = 8.4 min). However, during infusion of insulin + glucose the decline in the myocardial activity was prolonged and monoexponential. This data shows that insulin glucose, interfering with fatty acid metabolism, influences the myocardial washout of HDA, and thus support its use as a metabolic tracer.

Angiographic demonstration of tumor vascularity in left atrial myxoma: a case report.

We describe a 63-year-old woman with a large sessile left atrial myxoma and coexisting mitral valve stenosis and regurgitation. The diagnosis of a left atrial tumor was confirmed by echocardiography and coronary angiography. This case reveals the rare finding of tumor vascularity originating from both the right coronary artery and left circumflex artery.

[The leopard syndrome, a cardio-cutaneous syndrome]. / Das Leopardsyndrom, ein kardiokutanes Syndrom.

A patient with the "leopard" syndrome presented with cardiomyopathy and a large arteriovenous shunt of the left renal vessels. The skin manifestations included multiple lentigines, junctional naevi, blue naevi, and one malignant lentigo. This syndrome is a rare entity, but in all patients with multiple lentigines the possibility of associated cardiovascular changes should be considered. In addition, regular monitoring of the pigmented lesions should be performed because of the increased risk of development of malignant melanoma.

[Diagnostic value of 201-thallium imaging following dipyridamole in patients with a normokinetic left ventricle]. / Diagnostische Wertigkeit der 201-Thallium-Szintigraphie nach Dipyridamol bei Patienten mit normokinetischem Ventrikel.

In 100 patients with a normokinetic left ventricle 201-thallium imaging following administration of dipyridamole (0.50 mg/kg body wt. i.v.) showed a sensitivity of 67% (41/61) and a specificity of 95% (37/39) in diagnosing coronary artery disease. Exercise stress testing gave nearly equal sensitivity values (36/58 = 62%) with only slightly lower specificity (32/39 = 85%). The rate of true positive 201-thallium findings increased with the number of narrowed vessels (one vessel disease 50%, two vessel disease 63%, three vessel disease 94%); the extent of coronary artery disease was almost regularly underestimated with the scintigraphic method. Because of the low sensitivity a negative finding cannot exclude the presence of coronary artery disease, but the existence of three vessel disease can be considered improbable in patients in whom thallium scintigraphy findings are negative. Analysis following Bayes' theorem revealed the method to have a low diagnostic value in patients with either very low or high pretest probability for the disease; either a positive or a negative finding is of most use in a patient with low or average pretest probability of the disease (20-60%).