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W Voelker

Publications and source records attributed to W Voelker.

At least 37 records · Page 2Linked to original sources
PubMed1998

Accuracy of computer-based quantification of aortic valve stenosis.

In patients with aortic valve stenosis, the quantification of stenosis is usually performed using fluid-filled catheters and a computerized calculation program. The aim of this study was to determine the accuracy of this technique in comparison to the manual planimetry of the area between the curves of a simultaneous registration, using a multitip micromanometer catheter. The study was performed in 19 patients, in whom left and right heart catheterization was warranted. Systolic left ventricular and aortic peak pressures were significantly overestimated using a fluid-filled catheter (206 +/- 35 vs. 199 +/- 37 mm Hg, P = 0.0003, and 148 +/- 18 vs. 143 +/- 21 mm Hg, P = 0.0052). However, peak-to-peak pressure gradients were identical comparing both techniques (58 +/- 31 vs. 56 +/- 32 mm Hg, r = 0.983). The mean pressure gradients and aortic valve areas based on simultaneous measurements of left ventricular and aortic pressures by micromanometer catheters were identical to the values determined by a computer-based program using fluid-filled catheters (54 +/- 21 vs. 52 +/- 21 mm Hg, r = 0.923, P < 0.05, and 0.75 +/- 0.25 vs. 0.77 +/- 0.25 cm2, r = 0.935). Thus, the conventional use of fluid-filled catheters and of a computerized calculation of aortic valve area is valid for quantification of aortic stenosis in patients with sinus rhythm and without significant aortic regurgitation.

Adult↗
PubMed1998

Local and systemic delivery of low molecular weight heparin following PTCA: acute results and 6-month follow-up of the initial clinical experience with the porous balloon (PILOT-study). Preliminary Investigation of Local Therapy Using Porous PTCA Balloons.

The purpose of this study was to assess safety and feasibility of intracoronary delivery of reviparin using a porous balloon following percutaneous transluminal coronary angioplasty. The 2.7 mm porous balloon used in this study had 35 holes arranged in a spiral pattern. Eighteen patients (male n = 10, female n = 8, age 63 +/- 9 years) undergoing successful PTCA in coronary arteries with a vessel diameter of 2.5 to 3.0 mm determined by online QCA (LAD = 11, RCX = 3, RCA = 4) were included. They received a bolus of 7,000 anti-Xa-IU reviparin followed by local delivery of 1,500 anti-Xa-IU in 4 ml with an injection pressure of 2 atm. The patients received additionally 10500 anti-Xa-units intravenously during the following 24 hours and a daily dose of 7000 anti-Xa-units reviparin subcutaneously for the following 28 days. Angiograms were obtained before and after PTCA, directly after local delivery, at 24 hours postintervention and after 6 months. The primary success rate was 100%. Quantitative coronary angiography showed a minimum luminal diameter of 0.42 +/- 0.14 mm before PTCA, 1.87 +/- 0.45 after PTCA, 1.67 +/- 0.43 after LDD, 1.63 +/- 0.46 after 24 hours, and 1.06 +/- 0.6 after 6 months. Angiographic follow-up was obtained in all patients. No major complications occurred during the 6-month follow-up period. The angiographic restenosis rate was 28% (5/18) at follow-up. This study demonstrates safety and feasibility of local intracoronary delivery of reviparin with a porous balloon following PTCA even in smaller diameter coronary arteries.

Aged↗
PubMed1998

[Optimal expansion of the multi-link stent. An in vitro study with high resolution roentgen technique].

It has been speculated that high pressure implantation may improve the results of coronary stenting. However, this method bears the risk of persistent dissection and may increase late lumen loss. Presently, there is no consensus about the optimal stent implantation technique with the regard to balloon size and pressure. To elucidate this question an experimental study was performed in a coronary stenosis model. 3.5 mm Multi-Link (ML) stents were implanted in 3.3 mm silicone rubber tubes containing 50% concentric narrowings. Three implantation techniques were applied: 1. The standard technique using the conventional ML delivery system with a compliant balloon (ML-ST). 2. A new deployment method with a high pressure delivery system (ML-HP). 3. "Focal postdilation" using the ARC catheter, which has a special balloon with an inner compliant and an outer non-compliant section (ML-ARC). For comparison, the Palmaz-Schatz stent was implanted by using a high pressure balloon. Stent expansion was imaged by magnification radiography. Minimal lumen diameter within the stent (MLD) and the lumen diameter outside the stent (BD) were measured after dilations with 6, 9, 12, 15, 18, and 21 atm. The relation of the BD to the MLD was used as an index of vessel trauma. The results lead to the following conclusions: 1. A complete apposition to the vessel wall for a balloon/vessel relation of 1.1:1 could not be reached with pressures below 9-15 atm. The increase of the pressure beyond 15 atm resulted only in a minimal additional lumen. 2. Compared to the Palmaz-Schatz stent the recoil of the ML stent was significantly lower. 3. For all three implantation techniques the ML-ARC showed the best results with the maximal dilation of the stenotic vessel-area and the minimal expansion of the vessel outside the stent.

Angioplasty, Balloon, Coronary↗
PubMed1998

Acute and one year follow-up results after vessel size adapted PTCA using intracoronary ultrasound.

AIMS: Recent randomized clinical trials have reported a reduction in restenosis with intracoronary stents and have suggested that this restenosis reduction is a result of the higher immediate luminal gain, in comparison to conventional percutaneous transluminal coronary angioplasty (PTCA). The hypothesis of this study is based on the assumption that PTCA results may be optimized by determining vessel dimensions before intervention, using intravascular ultrasound. This may lead to long-term PTCA results equivalent to PTCA and the additional placement of a stent. The purpose of this prospective non-randomized single-centre study was to evaluate (1) the safety and efficacy and (2) the long-term outcome of vessel-size adapted PTCA in patients with native coronary artery obstructions. METHODS AND RESULTS: From January 1995 to December 1995 the morphological dimensions of target lesions were determined in 144 patients with 152 lesions by intravascular ultrasound prior to conventional balloon angioplasty. Quantitative assessment of the vascular dimensions were assessed on-line and the diameter of the balloon catheter was adapted to the external elastic membrane diameter at the lesion site. Using this strategy, mean balloon diameter was 4.0 +/- 0.5 mm and mean pressure for complete balloon expansion was 7 +/- 2 atmospheres. Acute and one year follow-up results were obtained in all 144 patients. Acute events occurred in two patients (one death and one acute surgical revascularization). During one year follow-up, 16 patients (12%) had a clinical event including one cardiac death, two transmural myocardial infarctions, 10 repeat PTCAs within the target lesion and three elective coronary artery bypass grafts (CABG). In 75% (n:112) control angiography was performed and revealed an angiographic restenosis rate of 21% using the NHLBI criteria of a diameter stenosis > 50%. CONCLUSION: Intravascular ultrasound provides an accurate and precise description of vascular dimensions at the site of the stenotic lesion. The use of balloon diameters following these measurements appears to be (1) safe in the acute setting with a low number of in hospital events and (2) gives a low restenosis rate and number of clinical events at one year follow-up. These promising results warrant verification in larger-scale randomized trials.

Aged↗
PubMed1998

Lesion morphology assessed by pre-interventional intravascular ultrasound does not predict the incidence of severe coronary artery dissections.

AIMS: Coronary artery dissections are common findings following percutaneous transluminal coronary angioplasty and occur with an incidence of approximately 20% to 40%. The purpose of this study was to evaluate the impact of intravascular ultrasound for the prediction of severe dissections by pre-interventional analysis of lesion morphology and plaque composition. METHODS AND RESULTS: Pre- and post-interventional intravascular ultrasound was performed in 197 patients with 205 lesions. Using intravascular ultrasound criteria, 24 lesions were classified as soft (hypo- or iso-echogenic), 73 as intermediate (hyper-echogenic) and 108 as calcified (calcific arc > 90 degree of the vessel circumference). Additionally, calcium localization was defined as subendothelial, central or deep. The incidence of dissections was 37.5% in patients with soft lesions, 24.7% in patients with intermediate and 36.1% in patients with calcified lesions. In calcified lesions, the occurrence of severe dissections was not dependent on the localization of calcium deposits. The procedural parameters were similar in all patients. The minimal inflation pressure, however, was significantly higher in calcified lesions (P < 0.01). CONCLUSION: Assessment of lesion morphology by intravascular ultrasound cannot predict the occurrence of severe dissections following percutaneous transluminal coronary angioplasty. Furthermore, despite significantly higher inflation pressures in heavily calcified lesions, the incidence of dissections was found to be comparable in all lesions.

Adult↗
PubMed1997

Evaluation of signal-averaged cardiokymography for the detection of ischaemic left ventricular dysfunction.

UNLABELLED: Cardiokymography (CKG) is a non-invasive method for the detection of patients with coronary artery disease (CAD). Issues of the present study were to evaluate the feasibility, sensitivity and specificity of a recently developed signal-averaged CKG system for detecting patients with pharmacologically induced ischaemic left ventricular wall motion abnormalities (WMA) during pharmacologic stress echocardiography (SE). Precordial CKG curves were recorded in 100 consecutive patients who underwent dobutamine-SE for suspected CAD. For interpretation, CKG curves were classified into three different types, depending on the degree of systolic outward motion. CKG test results were regarded as positive (indicating myocardial ischaemia) if there was a change of the baseline CKG type at peak pharmacologic stress. The CKG test results were positive in 18 of 27 patients with a pathologic dobutamine-SE (sensitivity 67%), but did not show any change of the prior CKG type in 57 of 69 patients with a normal SE (specificity 83%). Patients with a true positive CKG test had significantly (P<0.05) more echocardiographic segments with WMA than patients with a false negative CKG test. CONCLUSIONS: Signal-averaged CKG can detect patients with ischaemic ventricular dysfunction. Sensitivity of CKG in detecting patients with WMA depends on the extent of left ventricular ischaemia. Further studies are needed to define the diagnostic value of signal-averaged CKG in the non-invasive detection of patients with suspected CAD.

Adult↗
PubMed1997

Detection of patients with restenosis after PTCA by dipyridamole-atropine-stress-echocardiography.

Stress-echocardiography (SE) has been proven to be a valuable method for the diagnosis of coronary artery disease. For patients who cannot exercise, pharmacological stress-echocardiography represents an alternative method for the induction of cardiovascular stress. Few studies exist concerning the value of dipyridamole-SE for the detection of restenosis in patients after primary successful PTCA. It has been demonstrated that the addition of atropine can significantly increase the diagnostic potential of dipyridamole-SE, especially in patients with 1- or 2-vessel disease. The purpose of our study was to investigate the diagnostic value of high-dose dipyridamole-SE plus atropine (DASE) for the detection of restenosis after primary successful PTCA. We investigated 65 patients 3-6 months after PTCA before a control angiography was performed. Restenosis was defined as > 70% lumen narrowing, determined by quantitative coronary angiography. In 20/27 patients with restenosis, the DASE was pathological (sensitivity 74%); in 34/38 patients without restenosis the DASE was normal or showed no induced WMA (specificity 89%). Patients with tight restenosis (> 90%) were always correctly detected by DASE. Concerning the different vessels, restenosis of the LAD was correctly predicted by DASE in 11/12 patients, restenosis of the LCX in 6/9 patients and restenosis of the RCA in 8/11 patients. From the results of our study we conclude that DASE is a reliable diagnostic method for the non-invasive evaluation of patients after PTCA. DASE can identify patients with relevant restenosis after PTCA and help to select those patients who will probably benefit from further coronary interventions, for repeat angiography.

Angioplasty, Balloon, Coronary↗
PubMed1996

Comparison of passive and active perfusion catheters: an in vitro study in a pulsatile coronary flow model.

Perfusion balloon catheters are designed to provide continuous transcatheter blood flow and thereby reduce myocardial ischemia during coronary angioplasty. To compare the transcatheter flow rates of active and passive (auto-) perfusion catheters, a well-controlled experimental study was performed in a circulation model that duplicates the phasic, predominantly diastolic flow pattern of the left coronary artery. Mean diastolic coronary driving pressure varied between 20 and 100 mm Hg. For the autoperfusion catheters, a strong relationship between transcatheter flow and diastolic coronary driving pressure was found. For example, a coronary driving pressure of 80 mm Hg provided a coronary flow of 30 ml/min (RX-Perfusion [RP], ACS), 28 ml/min (Speedflow [SF], Schneider), 20 ml/min (Lifestream [LS], ACS), and 19 ml/min (Flowtrack [FT], ACS). Reduction of driving pressure to 40 mm Hg decreased the absolute transcatheter flow, which was now 16 ml/min (RP), 13 ml/min (SF), and 10 ml/min (LS and FT). The relative catheter flow (the ratio of absolute flow to baseline coronary flow rate without a catheter in place), was independent of actual coronary driving pressure and ranged between 21% +/- 1% (RP) and 14% +/- 1% (FT and LS). For the active perfusion system (Coreflo, Leocor, a maximal transcatheter flow of 82 ml/min was found. Using this active perfusion system, the relative catheter flow increased with decreasing coronary driving pressure:80 --> 40 mm Hg: 56% --> 107%. For all catheters, the distal perfusion decreased between 30% (3.0 mm RP) and 50% (3.0 mm LS) by a 0.014-inch guidewire placed through the inner channel of the catheter. Because of the strong relationship between coronary driving pressure and transcatheter flow, the residual flow through all autoperfusion catheters becomes critical (<20 ml/min), when the coronary driving pressure drops below 50 mm Hg. By contrast, active perfusion systems are independent of the actual coronary driving pressure and are therefore advantageous for prolonged dilation in patients with low aortic pressure.

Angioplasty, Balloon, Coronary↗
PubMed1996

Exercise Doppler echocardiography in conjunction with right heart catheterization for the assessment of mitral stenosis.

RATIONALE: A new diagnostic approach is reported, which combines Doppler echocardiography and a thermodilution technique for the calculation of mitral valve area at rest and during exercise. This method was applied to determine the magnitude of mitral valve reserve (= exercise-induced increase of mitral valve are) and to assess the hemodynamic relevance of mitral stenosis. METHODS: 69 patients with mitral stenosis were included in this study. A Swan-Ganz catheter was used to measure exercise hemodynamics and transvalvular flow by a thermodilution technique. The mean transmitral flow velocity vmean was determined by continuous wave Doppler. Measurements were performed simultaneously at rest and during stepwise bicycle ergometry. Effective mitral valve area was calculated according to the continuity equation method (MVACE = Flow/vmean). RESULTS: A significant exercise-induced increase of mitral valve area was found in the total group (rest-->25 W: 1.1 +/- 0.3-->1.3 +/- 0.4 cm2, p < 0.001). Two subgroups were defined according to the presence or absence of mitral valve reserve: delta MVA > and = 20%: group A (n = 30); delta MVA < 20%: group B (n = 39). Both groups did not differ with regard to mitral valve area at rest. However, the increase of cardiac output and stroke volume was significantly higher in group A than in group B. An effective mitral valve area at 25 W of less than 1.2 cm2 had an 80% sensitivity and an 83% specificity to detect a severe mitral stenosis. CONCLUSIONS: Because the presence and extent of mitral valve reserve cannot be predicted under resting conditions measurements under flow-increasing interventions are necessary. Our data demonstrate that exercise Doppler in conjunction with right-sided cardiac catheterization is most useful to determine mitral valve reserve and to assess the hemodynamic relevance of mitral stenosis.

Adult↗
PubMed1996

-Diagnostic shunt oximetry of atrial septal defect in adulthood-.

UNLABELLED: There are several circumstances in which data obtained at catheterization should alert the cardiologist to look for a shunt that had not been suspected previously. Aim of the study was to explore the most sensitive parameter which is easily practicable and which gives strong evidence for an atrial septal defect (ASD). Moreover, a simplified method for quantifying left-to-right shunts was analyzed. In 84 patients (58 with an atrial septal defect and 26 patients without shunt) a complete oxygen saturation status was determined. The oxymetrically determined relation between pulmonary bloodflow QP and systemic bloodflow QS was 1.31 to 5.60 in patients with ASD and 0.75 to 1.19 in patients without shunt. The analysis of sensitivity and specificity was determined to define the marginal value which gives suspicion of an ASD. The best values for sensitivity and specificity was found for PA O2-SVC O2 = 7.4% (sens. = 98.3%, spec.= 96.2%), PA O2 -IVC O2 = 2.0% (sens./spec.= 100%), PA O2 - MV O2 = 5.0% (sens./spec.= 100%) and PA O2 = 78.4% (sens./spec. = 97.5%). The correlation between the modified ratio QP/QS and various differences in O2-saturation with the shunt size was examined. A high correlation was found for the modified QP/QS with SVC O2 instead of MV O2 (r = 0.98), PA O2-SVC O2 (r = 0.77) and PA O2 - MV O2 (r = 0.74) with QP/QS, respectively. CONCLUSION: The results demonstrate that an O2-saturation >78% in the pulmonary artery is highly suspicious for the diagnosis of an ASD. With the modified ratio QP/QS = (ART O2-SVC O2)/(PV O2-PA O2) a high sensitive and specific modus of quantifying shunts can be reached. Determination of oxygen saturation from the V. cava interior is therefore not useful.

Adolescent↗
PubMed1996

Tricuspid valve endocarditis due to a jet lesion detected by echocardiography in a 27-year old man with congenital ventricular septal defect.

The case of an non-addict young caucasian with isolated tricuspid valve endocarditis in congenital ventricular septal defect (VSD) is presented. Despite antibiotic treatment the patient suffered from recurrent right sided pneumonias. A computed tomography of the chest revealed an abscess localized in the right lower lung with signs of cavitation. Echocardiography identified a vegetation located at the anterior tricuspid leaflet due to a jet lesion through the VSD. ECG-gated MRI revealed normal left ventricular function and localized the septal defect and a jet against the anterior tricuspid valve leaflet. The patient underwent open heart surgery and the VSD was closed. Now, two years later, the patient is free from any symptoms or complications. This case illustrates that noninvasive techniques like echocardiography and ECG-gated MRI can not only accurately image cardiac anatomy in patients with ventricular septal defect but additionally provide information about the pathomechanism of the development of jet lesions resulting in valvular vegetations. Operative correction of underlying cardiac disease in nonaddicts with complicating tricuspid valve endocarditis might be a favourable treatment especially when antibiotic treatment fails to cure the infection.

Adult↗
PubMed1995

Comparison of valvular resistance, stroke work loss, and Gorlin valve area for quantification of aortic stenosis. An in vitro study in a pulsatile aortic flow model.

BACKGROUND: Valvular resistance and stroke work loss have been proposed as alternative measures of stenotic valvular lesions that may be less flow dependent and, thus, superior over valve area calculations for the quantification of aortic stenosis. The present in vitro study was designed to compare the impacts of valvular resistance, stroke work loss, and Gorlin valve area as hemodynamic indexes of aortic stenosis. METHODS AND RESULTS: In a pulsatile aortic flow model, rigid stenotic orifices in varying sizes (0.5, 1.0, 1.5 and 2.0 cm2) and geometry were studied under different hemodynamic conditions. Ventricular and aortic pressures were measured to determine the mean systolic ventricular pressure (LVSPm) and the transstenotic pressure gradient (delta Pm). Transvalvular flow (Fm) was assessed with an electromagnetic flowmeter. Valvular resistance [VR = 1333.(delta Pm/Fm)] and stroke work loss [SWL = 100.(delta Pm/LVSPm)] were calculated and compared with aortic valve area [AVA = Fm/(50 square root of delta Pm)]. The measurements were performed for a large range of transvalvular flows. At low-flow states, flow augmentation (100-->200 mL/s) increased calculated valvular resistance between 21% (2.0 cm2 orifice) and 66% (0.5-cm2 orifice). Stroke work loss demonstrated an increase from 43% (2.0 cm2) to 100% (1.0 cm2). In contrast, Gorlin valve area revealed only a moderate change from 29% (2.0 cm2) to 5% (0.5 cm2). At physiological flow rates, increase in transvalvular flow (200-->300 mL/s) did not alter calculated Gorlin valve area, whereas valvular resistance and stroke work loss demonstrated a continuing increase. Our experimental results were adopted to interpret the results of three clinical studies in aortic stenosis. The flow-dependent increase of Gorlin valve area, which was found in the cited clinical studies, can be elucidated as true further opening of the stenotic valve but not as a calculation error due to the Gorlin formula. CONCLUSIONS: Within the physiological range of flow, calculated aortic valve area was less dependent on hemodynamic conditions than were valvular resistance and stroke work loss, which varied as a function of flow. Thus, for the assessment of the severity of aortic stenosis, the Gorlin valve area is superior over valvular resistance and stroke work loss, which must be indexed for flow to adequately quantify the hemodynamic severity of the obstruction.

Aortic Valve↗
PubMed1995

Perforation of a side branch of the right coronary artery during selective coronary angiography using 5 French Judkins catheters.

In this case report the first known case of a perforation of a side branch of the right coronary artery during diagnostic coronary angiography using 5 French Judkins catheters is described which occurred by selective intubation. Although catheter placement was controlled by contrast test injection the catheter occasionally intubated the conus artery super selectively just prior to the diagnostic injection. Thus, perforation of small side branches may be encountered especially by the use of 5 French Judkins catheters.

Cardiac Catheterization↗
PubMed1995

Double-blind comparison of the acute effects of two relevant doses of oral nicorandil on central hemodynamics, left ventricular function, and myocardial contractility.

Nicorandil is a nicotinamide derivative with potent vasodilator properties. Oral and sublingual administration of this compound in patients with coronary artery disease resulted in a predominant reduction of afterload and a small decrease in left ventricular preload. The effects of nicorandil in different doses on contractile left ventricular (LV) function, however, are not well defined. The aim of the present study was to assess the effects of nicorandil on hemodynamics, left ventricular volume and function, as well as the LV contractility index dP/dt measured by Millar-tip manometers. A total of 16 patients with coronary artery disease were included in this study. After diagnostic coronary angiography and ventriculography, the patients randomly received either 10 or 20 mg of oral nicorandil. The hemodynamic parameters, cardiac output, and LV end-diastolic and systolic pressures were determined after 15, 30, and 60 minutes, and a second angiogram was performed 60 minutes after administration. The predominant effect was a decrease in the mean aortic pressure with a concomitant decrease in the peripheral arterial resistance. Clinically relevant changes in aortic pressure, systemic vascular resistance, and rate-pressure product, however, were documented only after oral administration of 20 mg nicorandil, as opposed to minimal changes in the 10 mg group. LV volume and cardiac output were not changed significantly. LV contractility remained unchanged during the observation period. The hemodynamic profile of this compound is dose-dependent afterload reduction without a change in contractility. Because there was no concomitant increase in heart rate, calculated oxygen consumption was reduced, especially in the higher dose group.

Adult↗
PubMed1995

Intracoronary ultrasound following excimer-laser angioplasty. An in-vitro study in human coronary arteries.

UNLABELLED: To study the ablation effects induced by excimer laser coronary angioplasty (ELCA), we examined 41 segments of nine isolated coronary arteries. An electronic intracoronary ultrasound device (ICUS: 20 MHz, 3.5F, Endosonics) was positioned coaxially within the vessel. Angioplasty was performed using a 1.7 mm ELCA catheter (Spectranetics) which was placed in the lumen and directed vertically onto the intimal surface of the vessel (fluence: 10-50 mJ.mm-2). The laser catheter was removed after each lasing cycle to allow the stepwise evaluation of the morphological effects of ELCA and to avoid reaching the adventitia. Ultrasound images were compared with the corresponding histological specimens. In all cases, the ablation site could be correctly identified by ICUS. No penetration of the adventitia was seen at histology. Ablation depth was 0.31 +/- 0.18 mm as determined by histology and 0.34 +/- 0.18 mm as determined by ultrasound; the diameter of the crater was 0.63 +/- 0.21 mm, and 0.75 +/- 0.16 mm, respectively, and wall thickness was 0.68 +/- 0.18 mm, and 0.83 +/- 0.20 mm, respectively. A statistical relationship between ultrasonic and histology measurements was only found, however, for assessment of wall thickness (r = 0.71). CONCLUSIONS: The identification of small ablation effects by ICUS was possible with great accuracy and ELCA could be performed without penetration of the adventitial layers. However, exact quantification of the crater dimensions was not possible due to limitations of the axial and lateral resolution. Thus, for the guidance of ELCA by ICUS a further improvement in the resolution capabilities of ICUS devices is mandatory.

Angioplasty, Laser↗
PubMed1994

In vitro assessment of luminal dimensions of coronary arteries by intravascular ultrasound with and without application of echogenic contrast dye.

To evaluate the impact and limitations of intracoronary ultrasound in the assessment of lumen, we examined 80 segments of 20 isolated coronary arteries with a mechanical ultrasound device (CVIS) comparing the results of ultrasound with the corresponding histological specimens. Ultrasound was performed with and without echogenic contrast dye (Laevovist, Schering AG, FRG). After application of contrast dye, correlation of luminal area between histology and ultrasound was improved from r = 0.85 to r = 0.89 (p = ns). Accuracy of lumen measurements was low in segments < 2.5 mm; only after application of contrast dye a relationship between ultrasound and histological measurements was found. In all cases in which a deviation of more than 20% between ultrasound and histology was observed, this deviation could be reduced by the application of contrast dye. There are considerable limitations in the accuracy of ultrasound measurements in the near field. Thus, further improvement of intracoronary ultrasound devices is mandatory. However, with the use of the currently available systems, additional application of echogenic contrast dye can improve accuracy of luminal measurements, especially in smaller size vessels.

Adult↗
PubMed1994

Primary systemic amyloidosis leading to advanced renal and cardiac involvement in a 30-year old man.

The case of a 30-year-old man with primary systemic amyloidosis is reported. Three months prior to admission the patient developed fever, night sweats, dyspnea, and bilateral ankle swelling. Recurrent left-sided pleural effusion led to further investigation when massive proteinuria with free monoclonal lambda chains in the urine became evident. Abdominal subcutaneous fat aspiration and renal biopsy confirmed the diagnosis of amyloidosis. Bone marrow biopsy and bone scan did not reveal multiple myeloma. Echocardiography showed a sparkling texture of the interventricular septum. Pulsed-wave Doppler recording of the left ventricular inflow profile showed the pattern of advanced cardiac amyloidosis consistent with markedly impaired diastolic heart function. Electrocardiogram-gated magnetic resonance imaging was carried out for noninvasive evaluation of cardiac function. The patient was started on repeated courses of melphalan, prednisone, and colchicine therapy. Despite increasing deterioration of renal function the therapy was tolerated quite well, and the patient is still alive 10 months after initial diagnosis. Although very rare in this age, primary systemic amyloidosis should be considered as a cause of pleural effusion, proteinuria, and congestive heart failure and should lead to further investigation.

Adult↗