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H Lambertz

Publications and source records attributed to H Lambertz.

At least 19 recordsLinked to original sources
PubMed2005

Shortening the stent length reduces restenosis with bare metal stents: matched pair comparison of short stenting and conventional stenting.

OBJECTIVE: To investigate the effect of reducing stent length on the rate of target lesion restenosis. DESIGN: In a prospective investigation, acute and long term results of a short stenting procedure were analysed by quantitative angiography and compared with results of a conventional stenting procedure selected according to a matched pairs analysis. PATIENTS: Short stents were implanted in 400 consecutive patients with 464 lesions and conventional stents in 430 patients. Demographic and lesion characteristics were comparable between groups. INTERVENTIONS: In short stenting, the shortest stent length to cover only segments with > 30% reduction in vessel diameter was used. In conventional stenting, full coverage of a stenotic vessel segment was intended. MAIN OUTCOME MEASURES: The mean stent lengths of the short stent group (9.8 (4) mm) and the conventional stent group (16.3 (7) mm) differed significantly (p < 0.0001); all other procedural and angiographic parameters were the same. Procedural success was similar for both groups. Control angiography after six months was conducted in 92% of patients. RESULTS: Short stenting resulted in both less restenosis (68 of 431 (15.8%)) than conventional stenting (93 of 381 (24.4%), p = 0.007) and less late lumen loss (0.6 (0.6) mm v 0.75 (0.5) mm, p = 0.0001). Residual stenosis (< 45%) in adjacent vessel segments after short stenting did not affect the restenosis rate. Only the implantation of a < or = 9 mm stent predicted the absence of restenosis in a multivariate analysis. CONCLUSION: Shortening the length of bare metal stents reduces the restenosis rate as compared with conventional stenting.

Angina Pectoris↗
PubMed2004

[Non-invasive assessment of coronary flow reserve - valuable functional information in cardiac workflow].

Coronary flow reserve can be determined echocardiographically in the LAD in about 90 % and in the RCA in more than 80 % of patients respectively by the use of modern high-resolution ultrasound equipment. For this purpose either high frequency fundamental imaging or echo-contrast enhanced harmonic Doppler technology is used. The main advantage of the method lies in its noninvasiveness and the lack of radiation exposure. In combination with coronary morphologic findings obtained from heart catheterization, CFR is helpful in the planning of further invasive procedures for coronary artery disease and in the estimation of the prognosis of such procedures. The functional status after PTCA of LAD/RCA or mammary bypass surgery can be evaluated during follow-up monitoring. Alteration in the coronary microcirculation can also be discovered in a non-invasive way, improvement of microcirculatory disorders by adequate therapy can be assessed by serial measurements of CFR.

Angioplasty, Balloon, Coronary↗
PubMed2003

[Sildenafil does not change coronary flow reserve in diabetics with erectile dysfunction].

BACKGROUND AND AIM OF STUDY: Disturbance of the microvascular coronary circuit is common in diabetics with erectile dysfunction. We investigated effects of sildenafil on coronary flow reserve (CFR) of the left anterior descending branch. PATIENTS AND METHODS: 43 diabetics (aged 59 +/- 7 years) with erectile dysfunction and without symptoms of coronary artery disease were selected. Cardiac diagnosis, including stress ECG and echocardiography was performed in all. Because of the clinical suspicion of coronary artery disease coronary angiography was performed in 16 of them. Severe coronary artery disease was confirmed in 12 patients who were excluded from further analyses as well as 10 diabetics in whom coronary flow measurements were not possible. In the other 21 diabetics, adenosine-mediated CFR was calculated at baseline and 1 hour after ingestion of 50 mg sildenafil by transthoracic Doppler echocardiography. RESULTS: CFR at baseline was at the lower level of the normal range in 17/21 diabetics (median 245 %, range 210 - 490 %). CFR decreased insignificantly in 12/21 patients after sildenafil administration (Delta CFR -10 %, p = 0.3). Patients with a body mass index > 25 kg/m(2), and left ventricular hypertrophy had the highest reduction of CFR after sildenafil, but a drop of the CFR below 200 % was not observed in any patient. Systemic blood pressure dropped significantly from 130/80 mmHg to 120/72 mmHg (p < 0.002). CONCLUSION: Diabetics with erectile dysfunction often have a CFR in the lower range of normal. Sildenafil did not further reduce CFR. Asymptomatic, severe coronary artery disease often can be found in diabetics with erectile dysfunction. Cardiological screening for contraindications for sildenafil seems mandatory in diabetics with a high cardiovascular risk profile.

Adult↗
PubMed2003

[Non-invasive assessment of coronary flow reserve--valuable functional information in cardiac workflow].

Coronary flow reserve (CFR) can be determined echocardiographically in the LAD in about 90% and in the RCA in more than 70% of patients, respectively, by the use of modern high-resolution ultrasound equipment. For this purpose either high frequency fundamental imaging or echo-contrast enhanced harmonic Doppler technology is used. The main advantage of the method lies in its noninvasiveness and the lack of radiation exposure. In combination with coronary morphologic findings obtained from heart catheterization, CFR is helpful in the planning of further invasive procedures for coronary artery disease and in the estimation of the prognosis of such procedures. The functional status after PTCA of LAD/RCA or mammary bypass surgery can be evaluated during follow-up monitoring. Alteration in the coronary microcirculation can also be discovered in a non-invasive manner; improvement of microcirculatory disorders by adequate therapy can be assessed by serial measurements of CFR

Angioplasty, Balloon, Coronary↗
PubMed2000

[Echocardiographic measurements of coronary flow reserves in the left anterior descending artery allows detection of significant stenosis].

BACKGROUND AND OBJECTIVE: CFR has proven to be useful in the selection of patients undergoing invasive treatment of coronary artery disease and in estimating their prognosis. However, CFR could only be determined in everyday practice invasively during catheterization procedures. Recent development of high-resolution transthoracic color Doppler echocardiography (TTCD) allows transthoracic visualization of distal LAD and supra-apical intra-myocardial perforator branches, and non-invasive measurement of CFR. The feasibility of non-invasive assessment of coronary flow reserve (CFR) in the left anterior descending artery (LAD) using echo-enhanced high resolution TTCD was investigated. The results were compared with the degree of coronary diameter-stenosis obtained during cardiac catheterization. CFR was determined by measuring to ratio of pulsed wave Doppler time velocity integral during adenosine-induced hyperemia (140 micrograms/kg/min i.v.) to baseline value. If Doppler signal of LAD flow was insufficiently at basal condition, an echo enhancer (Levovist) was used. PATIENTS AND METHODS: 70 patients were examined by TTCD (7 MHz B-Mode, 5 MHz color Doppler, 3.5 MHz PW-Doppler) after coronary angiography had been performed. Gr I consisted of 14 patients without heart disease, Gr II of 26 patients with 40-75% isolated LAD diameter-stenosis, and Gr III of 30 patients with > 75% LAD diameter-stenosis. RESULTS: CFR could be quantified in 56/70 patients (80%), in 42/70 patients without echo enhancer, and in 14/28 patients with an echo-enhancing agent. CFR in Gr I was 3.84 +/- 0.57, in Gr II 2.31 +/- 0.20 (vs Gr I p < 0.01) and in Gr III 1.60 +/- 0.30 (vs Gr II p < 0.02). CONCLUSION: CFR of LAD can be determined in 80% of patients by the synergistic use of high resolution TTCD combined with intravenous given ultrasound echo-enhancing agent. A coronary flow reserve of less than 2.1 detected in this patient cohort significant LAD-stenosis with a sensitivity and specificity of 91% and 76%.

Adult↗
PubMed1999

Noninvasive assessment of coronary flow reserve with transthoracic signal-enhanced Doppler echocardiography.

OBJECTIVES: The feasibility of noninvasive assessment of coronary flow reserve (CFR) in the distal left anterior descending artery (LAD) with echocardiography-enhanced transthoracic pulsed wave Doppler guided by high-resolution transthoracic color Doppler (TTCD) was investigated. The results were compared with the degree of coronary diameter stenosis obtained during cardiac catheterization. BACKGROUND: Assessment of CFR has proven to be useful in the selection of patients undergoing invasive treatment of coronary artery disease and in estimating their prognosis. However, CFR could only be determined invasively in everyday practice during catheterization procedures. Recent development of high-resolution TTCD allows transthoracic visualization of distal LAD and supra-apical intramyocardial perforator branches and noninvasive measurement of CFR with pulsed wave Doppler technique. METHODS: CFR was determined by measuring the ratio of pulsed wave Doppler time velocity integral during adenosine-induced hyperemia (140 microgram/kg/min intravenously) to baseline value. If the baseline Doppler signal of LAD flow was insufficient, an echocardiography (echo) enhancer (Levovist) was used. Forty-five patients were examined by TTCD (7-MHz B-mode, 5-MHz color Doppler, and 3.5-MHz pulsed wave Doppler) after coronary angiography had been performed. Group 1 consisted of 15 patients without heart disease, group 2 of 15 patients with 50% to 85% isolated LAD diameter stenosis, and group 3 of 15 patients with >85% LAD diameter stenosis. RESULTS: Peripheral LAD coronary flow at baseline condition was assessed in 40 (88%) patients with TTCD. CFR could be quantified in 36 (80%) of the 45 patients: in 18 patients without echo enhancer, and in 18 patients with echo-enhancing agent. CFR could not be assessed in 9 (20%) patients. CFR in the various groups was as follows: group 1, 3. 13 +/- 0.57; group 2, 2.23 +/- 0.20 (vs group 1: P <.01); and group 3, 1.64 +/- 0.30 (vs group 2: P <.02). CONCLUSION: CFR in the LAD can be determined in 80% of patients with pulsed wave Doppler guided by high-resolution TTCD combined with intravenously administered echo-enhancing agent.

Aged↗
PubMed1998

[Circumscribed apical left ventricular hypertrophy. Dynamic development and long term progression].

HISTORY AND CLINICAL FINDINGS: A 64-year-old obese man had for 15 years suffered from exercise-independent retrosternal pressure sensation, radiating to the neck and back. Shortly after the onset of these symptoms he had undergone coronary angiography with negative results. But at that time the resting ECG showed discrete T wave negativity in the left precordial leads. INVESTIGATIONS: At the present admission the ECG showed deeply inverted T waves in the left precordial and limb leads and a positive Sokolow-Lyon index of 4.8 mV. Left ventricular angiography demonstrated in enddiastole a circumscribed myocardial hypertrophy limited to the apex and of typical "ace of spade" shape. DIAGNOSIS, TREATMENT AND COURSE: Left-heart catheterization and angiocardiography provided the diagnosis of circumscribed apical left ventricular hypertrophy (ALVH). As the patient had only minor symptoms no treatment was given. CONCLUSION: Circumscribed ALVH can show marked dynamic development in long-term observations. If there is marked T wave negativity, even with previously normal LV angiography, circumscribed ALVH should be included in the differential diagnosis. Patients with atypical angina pectoris and increasingly suggestive ECG changes should, even if previous coronary angiography had been negative, undergo transthoracic echocardiography with a high-frequency transducer, special attention being paid to muscular changes at the LV apex.

Angina Pectoris↗
PubMed1998

[Noninvasive determination of coronary flow reserve with signal enhanced high resolution transthoracic Doppler color echocardiography].

UNLABELLED: The feasibility of non-invasive assessment of coronary flow reserve (CFR) in the left anterior descending artery (LAD) using echo-enhanced high-resolution transthoracic color Doppler echocardiography (TTCD) was investigated. The results were compared with the degree of coronary diameter-stenosis obtained during cardiac catheterization. CFR has proven to be useful in the selection of patients undergoing invasive treatment of coronary artery disease and in estimating their prognosis. However, CFR could only be determined in everyday practice invasively during catheterization procedures. Recent development of high-resolution TTCD allows transthoracic visualization of distal LAD and supra-apical intramyocardial perforator branches, and non-invasive measurement of CFR. CFR was determined by measuring the ratio of pulsed-wave Doppler time velocity integral during adenosine-induced hyperemia (140 micrograms/kg/min i.v.) to baseline value. If Doppler signal of LAD flow was insufficiently at basal condition, an echo enhancer (Levovist) was used. 45 patients were examined by TTCD (7 MHz B-mode, 5 MHz color Doppler, 3.5 MHz PW Doppler) after coronary angiography had been performed. Group I consisted of 15 patients without heart disease, Group II of 15 patients with 40 to 70% isolated LAD diameter stenosis, and Group III of 15 patients with > 70% LAD diameter stenosis. Peripheral LAD coronary flow at baseline condition was assessed in 40 patients (88%) using TTCD. CFR could be quantified in 36/45 patients (80%), in 18 patients without echo enhancer, and in 18 patients with echo-enhancing agent. In 9/45 patients CFR could not be assessed. CFR in Group I was 3.13 +/- 0.57, in Group II 2.23 +/- 0.20 (vs Group I p < 0.01) and in Group III 1.64 +/- 0.30 (vs Group II p < 0.02). CONCLUSION: CFR of LAD can be determined in 80% of patients by the synergistic use of high-resolution TTCD combined with intravenous given ultrasound echo-enhancing agent.

Adult↗
PubMed1997

[Signal improvement of pulmonary venous Doppler flow prifile after intravenous injection of levovist].

The analysis of the pulmonary venous flow Doppler pattern can assist in the determination of the severity of mitral regurgitation and, in conjunction with transmitral flow pattern, the assessment of left ventricular diastolic dysfunction. In about one third of the cases, however, transthoracic ultrasonography is not able to record an adequately analyzable pulmonary venous flow pattern. The aim of the study was to examine and compare the effect of the echo-enhancing agent Levovist on the pulsed-wave Doppler flow quality of the transthoracically (TTE) and transesophageally (TEE) recorded pulmonary venous flow. In 26 consecutive patients, a qualitative (score system) and quantitative analysis of the pulmonary venous flow pattern was obtained before and after peripheral venous injection of Levovist at concentrations of 200 mg/ml (low dose) and 400 mg/ml (high dose). The number of measurable studies for the antegrade pulmonary venous flow increased after Levovist from 85% to 96% for TTE and from 96% to 100% for TEE. The retrograde flow as seen by TTE was adequately analyzable in only 45% before and in 73% after injection of Levovist (p < 0.02). Before any contrast enhancement, the retrograde pulmonary venous flow recorded by TEE could be analyzed in 77% of the patients with the percentage increasing to 88% and 92% after administration of a low and high dose of Levovist, respectively (p < 0.05). In particular, the quality score of the retrograde flow was significantly altered by the administration of Levovist (increase from 1.8 +/- 1.0 to 2.6 +/- 1.1 (low dose Levovist), p < 0.05 and to 2.7 +/- 1.3 (high dose Levovist). p < 0.05). The pulsed-wave Doppler evaluation by TTE without Levovist underestimated the velocities of the antegrade and retrograde pulmonary venous flow After administration of Levovist, the recorded values are comparable to those obtained by TEE. An analogous pattern is encountered when quantifying the duration of the retrograde flow component. Thus, the peripheral venous injection of Levovist leads to an improved quality of the pulmonary venous flow Doppler signal recorded by TTE. Qualitatively and quantitatively the values recorded by TTE after administration of Levovist are comparable to those of the TEE technique without an echo-enhancing agent.

Adult↗
PubMed1996

[Circumscribed apical left ventricular hypertrophy as the cause of a pronounced T-wave negativity].

HISTORY AND CLINICAL FINDINGS: Two patients, one aged 57 the other 44 years, complained of nonspecific symptom-palpitation, left precordial pain and dyspnoea. There were no contributory findings on physical examination in both cases. INVESTIGATIONS: Both patients had hyperlipoproteinaemia, the younger one hyperuricaemia as well. The electrocardiogram showed deeply negative symmetrical T waves in the precordial leads. Transthoracic and transoesophageal echocardiography demonstrated thickening of the apical left ventricular wall. Coronary heart disease was excluded in both patients by coronary angiography. TREATMENT AND COURSE: The findings were fully explained to both patients. As they had only minor symptoms, no specific treatment was given. CONCLUSION: Isolated apical left ventricular hypertrophy should be considered as a possible cause of marked T-wave inversion in the precordial leads; this special form of hypertrophic cardiomyopathy is rarely seen in Europeans. As autosomal dominant inheritance of this condition has been described in two families, other family members should be studied by echocardiography whenever this abnormality is found.

Adult↗
PubMed1996

[Tilt-table study in vasovagal syncope. The diagnostic gain from isoprenaline administration].

OBJECTIVE: The cause of syncope remains unclear in half of the cases, even after extensive neurological and cardiological examination. A study was, therefore, undertaken to determine the number of patients with the suspected diagnosis of vasovagal syncope that were confirmed by the tilting table test and how often it required the additional administration of isoprenaline to do so. PATIENTS AND METHODS: A tilting table test was performed on 75 patients (49 men, 26 women; mean age 41 [17-80] years) with syncopes of uncertain cause, previous examinations having failed to discover any neurological or cardiological cause. The test was done with a head-up angle of 60 degrees for 30 min. ECG and arterial blood pressure by indwelling catheter were recorded continuously. If the test was negative, isoprenaline was given intravenously at a rate of 5 micrograms/min during a five-minute period in the horizontal position, followed by 10 minutes at 60 degrees head-up position. RESULTS: Vasovagal syncope or presyncope was induced in 49 of the 75 patients during the tilting table test, a sensitivity of 65%. But 45% of the tests were positive only with the administration of isoprenaline, i.e. an increase in sensitivity to 81.5%. In 96% of the patients with a positive test there was conformity of symptoms between the induced and the spontaneously occurring syncopes. CONCLUSION: The tilting table test is a valuable means of investigating cases of syncope. More than half of the cases of syncope of uncertain cause can be correctly diagnosed classified in this way. The additional use of isoprenaline infusion greatly increases the sensitivity of the method.

Adolescent↗
PubMed1995

[Right ventricular thrombi in primary antiphospholipid syndrome].

Over a period of several months a 33-year-old man had recurrent pulmonary emboli. No thromboses could be demonstrated in the peripheral venous system. Transoesophageal echocardiography showed two spherical space-occupying structures in the right ventricle which were removed operatively under the suspected diagnosis of multilobular myxomas. However, their histological examination revealed pure thrombi that had grown by apposition. This unusual findings of right-ventricular thrombi could not be explained pre- and intraoperatively by any local thrombi-favouring changes in the right heart. Tests of clotting mechanisms demonstrated lupus anticoagulant (kaolin-clotting-time mixture test: LA index 21.7 [normal: < 15]), as well as an increased IgG cardiolipin antibody concentration of 19.3 U/l). As no underlying disease was discovered, the diagnosis was by definition primary antiphospholipid syndrome. No further thrombo-embolism has occurred during continuing oral anticoagulation with phenprocoumon.

Adult↗
PubMed1995

[Single right coronary artery with absence of the left coronary ostium].

We report the rare congenital anomaly of a singular right coronary artery in absence of the left coronary ostium. In a 31-years-old man, coronary arterial angiography demonstrated a right coronary artery which, arising from the right Sinus Valsalvae, first described the normal right coronary arterial course but in the apical region continued to follow, in reverse direction, the normal course of the left anterior descending artery. The proximal diameter of the vessel measured 5.2 mm. Thallium scintigraphy showed no ischemia of the anterior wall. The risk of developing circumscribed atherosclerosis due to anatomical reasons seems not to be increased, as no additional bifurcation nor kinking was to be found.

Adult↗
PubMed1994

Transoesophageal pacing echocardiography for detection of restenosis after percutaneous transluminal coronary angioplasty.

Non-invasive documentation of restenosis after successful percutaneous transluminal coronary angioplasty (PTCA) remains a problem. Thus, transoesophageal pacing echocardiography (TPE) with simultaneous rapid atrial pacing via the same probe, a recently validated method for detection of coronary artery disease, was used in 60 patients for detection of restenosis after successful PTCA (54 patients with one and six patients with multivessel PTCA). The patients came for routine follow-up angiography 5.4 +/- 3.7 months after PTCA regardless of clinical status. Restenosis (diameter stenosis > or = 50%) was demonstrated in 22 patients. Disease progression in previously normal vessels was noted in three additional patients. Results for detection of restenosis and disease progression were compared to exercise ECG and in 40 patients to Tc-99m methoxy-isobutyl-isonitrile (MIBI)-radionuclide perfusion imaging. Diagnostic standard exercise ECG could be performed in only 38 patients, due to peripheral vascular disease, joint disease or premature exhaustion in the rest of patients. TPE was non-diagnostic in two patients due to ineffective pacing or patient discomfort. Sensitivity of TPE for detection of restenosis and disease progression after PTCA was 84% compared with 50% and 86% for exercise ECG and Tc-99m MIBI-SPECT (P < 0.03 and ns), respectively. Specificity of TPE (85%) was also higher than that of exercise ECG (59%, P < 0.03) and comparable to the specificity of MIBI-SPECT (84%). Overall accuracy of TPE was far superior to exercise ECG and similar to MIBI-SPECT (84% vs 54% and 85%) (P = 0.0007 and ns, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1994

Altered left ventricular diastolic function post-atrial pacing in coronary artery disease and left ventricular hypertrophy: further insights by pulmonary venous flow analysis.

Left ventricular filling dynamics during acute pacing-induced myocardial ischaemia were assessed using transoesophageal atrial pacing and simultaneous Doppler measurements of pulmonary venous and mitral flow. All patients (10 with CAD and 12 with left ventricular hypertrophy due to hypertrophic cardiomyopathy; HCM) were in sinus rhythm and patients with mitral insufficiency were excluded. Data were compared with those of a control group (n = 10). Measurements were obtained at baseline (heart rate 84 +/- 14 beats.min-1) and immediately after atrial pacing via the same transoesophageal echocardiography (TEE) probe after stepwise increase of the pacing rate to 133 +/- 12 beats.min-1. Heart rate immediately after pacing was 83 +/- 13 beats.min-1. Time velocity integrals (TVI) were calculated at baseline and after pacing for the following flows: early (E) and late (A) mitral flows, as well as antegrade systolic (S), diastolic (D) and retrograde diastolic (R) pulmonary venous flows. In the control group none of the flow parameters changed significantly after pacing compared with baseline data. In contrast, in CAD patients, the TVI of the E wave, the TVI E/A ratio as well as the pulmonary venous flow changed significantly after pacing (7.3 to 5.5 cm, P < 0.05, 1.7 to 1.1, P < 0.01 and 1.0 to 2.1 cm, P < 0.001, respectively). HCM patients also showed significant changes: TVI E/A ratio post-pacing decreased from 1.9 to 1.4 (P < 0.05), and the pulmonary venous reverse flow integral increased from 1.3 to 2.8 cm (P < 0.0001). Analysis of variance showed the TVI E/A ratio to be significantly dependent on pacing (P = 0.012). The pulmonary venous retrograde flow was found to be influenced by the presence of disease (P = 0.033 before and P = 0.0001 after pacing) and in all cases by pacing (before vs after pacing; P = 0.0001). Pacing resulted in significantly different changes in the TVI E/A ratio and the TVI of the retrograde pulmonary venous flow for CAD and HCM patients compared with those of control subjects. In patients with CAD and HCM, rapid atrial pacing results in a decreased early to late ventricular filling ratio because of impaired relaxation, despite presumably increased filling pressure. Retrograde pulmonary venous flow increased because of increased filling pressure and operating left ventricular stiffness.

Adult↗
PubMed1994

[Comparison of conventional and miniaturized biplane echoscope: initial clinical results].

A subset of patients experiences substantial discomfort on examination with transesophageal echocardiography using the conventional echoscope, whereby the dimensions of the probe play a decisive role. Miniaturized biplane transducers have recently become available (2 x 32 crystals; dimensions 9.5 x 8.7 mm; circumference approx. 30% less than the conventional echoscope), which allow ultrasound examination at 3.5, 5.0 and 7.0 MHz. A prospective study was carried out in 70 patients to compare difficulties on insertion of the probe, subjective evaluation by the patient during examination, and the 2D-image as well as Doppler and color-coded Doppler quality of the miniaturized biplane echoscope. In 43 patients, intubation of the esophagus proved less difficult with the smaller instrument, it was more difficult in 8 cases. 54 patients reported that the discomfort was definitely easier to bear on use of the narrow instrument. Concomitant parasympathicolytic medication was needed with the smaller probe in 4 cases, and 11 times with the conventional echoscope. The quality of the 2D-image attained by the miniaturized probe was naturally lower. Employing multi-Hertz technology at a frequency of 7 MHz, however, imaging of the anatomy was excellent in the near field of 5-6 cm, and nearly equivalent to that of the conventional probe (5 MHz). The quality of PW-and CW-Doppler as well as color-coded Doppler information was identical. Whenever examination with a conventional echoscope promises to be difficult, or when sedation is contraindicated due to a severe illness or respiratory insufficiency, transesophageal echocardiography should be considered with a smaller biplane probe at higher frequencies.

Adolescent↗