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Shah AR, Khan MS, Hirahara AM, Lange M, Ranjan R, Dosdall DJ. A real-time system for selectively sensing and pacing the His-bundle during sinus rhythm and ventricular fibrillation. Biomed Eng Online 2020; 19:19. [PMID: 32276597 PMCID: PMC7146996 DOI: 10.1186/s12938-020-00763-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 04/01/2020] [Indexed: 11/18/2022] Open
Abstract
Background The His–Purkinje (HP) system provides a pathway for the time-synchronous contraction of the heart. His bundle (HB) of the HP system is gaining relevance as a pacing site for treating non-reversible bradyarrhythmia despite limited availability of tools to identify the HB. In this paper, we describe a real-time stimulation and recording system (rt-SRS) to investigate using multi-electrode techniques to identify and selectively pace the HB. The rt-SRS can not only be used in sinus rhythm, but also during ventricular fibrillation (VF). The rt-SRS will also help investigate the so far unknown causal effects of selectively pacing the HB during VF. Methods The rt-SRS consists of preamplifiers, data acquisition cards interfaced with a real-time controller, a current source, and current routing switches on a remote computer, which may be interrupted to stimulate using a host machine. The remote computer hosts a series of algorithms designed to aid in identifying electrodes directly over the HB, to accurately detect activation rates without over-picking, and to deliver stimulation pulses. The performance of the rt-SRS was demonstrated in seven isolated, perfused rabbit hearts. Results The rt-SRS can visualize up to 96 channels of raw data, and spatial derivative data at 6.25-kHz sampling rate with an input-referred noise of 100 µV. The rt-SRS can send up to ± 150 V of stimuli pulses to any of the 96 channels. In the rabbit experiments, HB activations were detected in 18 ± 6.8% of the 64 electrodes used during VF. Conclusions The rt-SRS is capable of measuring and responding to cardiac electrophysiological phenomena in real-time with precisely timed and placed electrical stimuli. This rt-SRS was shown to be an effective research tool by successfully detecting and quantifying HB activations and delivering stimulation pulses to selected electrodes in real-time.
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Affiliation(s)
- Ankur R Shah
- Department of Biomedical Engineering, The University of Utah, Salt Lake City, UT, 84112, USA.,Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, UT, 84112, USA
| | - Muhammad S Khan
- Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, UT, 84112, USA
| | - Annie M Hirahara
- Department of Biomedical Engineering, The University of Utah, Salt Lake City, UT, 84112, USA.,Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, UT, 84112, USA
| | - Matthias Lange
- Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, UT, 84112, USA
| | - Ravi Ranjan
- Department of Biomedical Engineering, The University of Utah, Salt Lake City, UT, 84112, USA.,Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, UT, 84112, USA.,Division of Cardiovascular Medicine, Department of Internal Medicine, The University of Utah, Salt Lake City, UT, 84112, USA
| | - Derek J Dosdall
- Department of Biomedical Engineering, The University of Utah, Salt Lake City, UT, 84112, USA. .,Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, UT, 84112, USA. .,Division of Cardiovascular Medicine, Department of Internal Medicine, The University of Utah, Salt Lake City, UT, 84112, USA. .,Division of Cardiothoracic Surgery, School of Medicine, Department of Surgery, The University of Utah, Salt Lake City, UT, 84112, USA.
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OKAMURA HIDEO, DESIMONE CHRISTOPHERV, KILLU AMMARM, GILLES EMILYJ, TRI JASON, ASIRVATHAM ROSHINI, LADEWIG DEJAEJ, SUDDENDORF SCOTTH, POWERS JOANNEM, WOOD-WENTZ CHRISTINAM, GRAY PETERD, RAYMOND DOUGLASM, SAVAGE SHELLEYJ, SAVAGE WALTERT, BRUCE CHARLESJ, ASIRVATHAM SAMUELJ, FRIEDMAN PAULA. Evaluation of a Unique Defibrillation Unit with Dual-Vector Biphasic Waveform Capabilities: Towards a Miniaturized Defibrillator. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2017; 40:108-114. [DOI: 10.1111/pace.12979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 10/14/2016] [Accepted: 10/25/2016] [Indexed: 11/29/2022]
Affiliation(s)
- HIDEO OKAMURA
- Division of Cardiovascular Diseases; Mayo Clinic; Rochester Minnesota
| | | | - AMMAR M. KILLU
- Division of Cardiovascular Diseases; Mayo Clinic; Rochester Minnesota
| | | | - JASON TRI
- Division of Cardiovascular Diseases; Mayo Clinic; Rochester Minnesota
| | | | | | | | - JOANNE M. POWERS
- Division of Cardiovascular Surgery; Mayo Clinic; Rochester Minnesota
| | | | - PETER D. GRAY
- Employees and equity owners in CardioThrive; Walnut Creek California
| | | | - SHELLEY J. SAVAGE
- Employees and equity owners in CardioThrive; Walnut Creek California
| | - WALTER T. SAVAGE
- Employees and equity owners in CardioThrive; Walnut Creek California
| | - CHARLES J. BRUCE
- Division of Cardiovascular Diseases; Mayo Clinic; Rochester Minnesota
| | | | - PAUL A. FRIEDMAN
- Division of Cardiovascular Diseases; Mayo Clinic; Rochester Minnesota
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Incidence and clinical predictors of low defibrillation safety margin at time of implantable defibrillator implantation. J Interv Card Electrophysiol 2012; 34:93-100. [DOI: 10.1007/s10840-011-9648-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2011] [Accepted: 11/15/2011] [Indexed: 11/27/2022]
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Loukas M, Tubbs RS. Intersection patterns of human coronary veins and arteries. Anat Sci Int 2008; 83:179-80; author reply 181. [DOI: 10.1111/j.1447-073x.2008.00237.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Dosdall DJ, Sweeney JD. Extended charge banking model of dual path shocks for implantable cardioverter defibrillators. Biomed Eng Online 2008; 7:22. [PMID: 18673561 PMCID: PMC2527568 DOI: 10.1186/1475-925x-7-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Accepted: 08/01/2008] [Indexed: 11/15/2022] Open
Abstract
Background Single path defibrillation shock methods have been improved through the use of the Charge Banking Model of defibrillation, which predicts the response of the heart to shocks as a simple resistor-capacitor (RC) circuit. While dual path defibrillation configurations have significantly reduced defibrillation thresholds, improvements to dual path defibrillation techniques have been limited to experimental observations without a practical model to aid in improving dual path defibrillation techniques. Methods The Charge Banking Model has been extended into a new Extended Charge Banking Model of defibrillation that represents small sections of the heart as separate RC circuits, uses a weighting factor based on published defibrillation shock field gradient measures, and implements a critical mass criteria to predict the relative efficacy of single and dual path defibrillation shocks. Results The new model reproduced the results from several published experimental protocols that demonstrated the relative efficacy of dual path defibrillation shocks. The model predicts that time between phases or pulses of dual path defibrillation shock configurations should be minimized to maximize shock efficacy. Discussion Through this approach the Extended Charge Banking Model predictions may be used to improve dual path and multi-pulse defibrillation techniques, which have been shown experimentally to lower defibrillation thresholds substantially. The new model may be a useful tool to help in further improving dual path and multiple pulse defibrillation techniques by predicting optimal pulse durations and shock timing parameters.
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Affiliation(s)
- Derek J Dosdall
- Department of Biomedical Engineering at the University of Alabama at Birmingham, Birmingham, Alabama, USA.
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Dosdall DJ, Rothe DE, Sweeney JD. Programmable arbitrary waveform generator for internal defibrillation research. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:3971-4. [PMID: 17271167 DOI: 10.1109/iembs.2004.1404109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
A programmable arbitrary waveform generator for creation of experimental defibrillation shocks is described. The system is capable of delivering shocks for internal defibrillation via 10 channels at 1000 Volts and 30 Amps. A microcontroller driven system that can receive waveform commands from a laptop was designed to be able to deliver shocks to any combination of electrodes. Waveforms are controllable down to 100 microsecond intervals and each channel is capable of serving as anode or cathode. This system can be used to verify predictions for defibrillation waveform efficacy as predicted by modeling efforts or to test new experimental waveforms tuned to parameters from an individual subject.
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Affiliation(s)
- D J Dosdall
- Harrington Department of Bioengineering, Arizona State University, Tempe, AZ, USA
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Loukas M, Tubbs RS, Jordan R. Aneurysm of the great cardiac vein. Surg Radiol Anat 2007; 29:169-72. [PMID: 17242871 DOI: 10.1007/s00276-006-0176-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Accepted: 12/04/2006] [Indexed: 11/28/2022]
Abstract
Anatomical variations in the cardiac veins have the potential to cause iatrogenic injuries during cardiac surgical procedures or cardiac resynchronization therapy. We present a case of an 86-year-old man, which presented with a great cardiac vein aneurysm. The great cardiac vein arose near the apex of the interventricular sulcus to the right of the anterior interventricular branch (AIB) of the left coronary artery and crossed the AIB anteriorly to the left. The great cardiac vein aneurysm appeared to be due to a possible distal constriction of the great cardiac vein by a small muscular branch of the circumflex branch and a possible proximal constriction by the left marginal artery. Cardiologists who interpret imaging of the cardiac veins and cardiac surgeons who operate close to the great cardiac vein should be aware of such a variation.
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Affiliation(s)
- Marios Loukas
- Department of Anatomical Sciences, St. George's University School of Medicine, Grenada, West Indies.
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Paisey JR, Yue AM, Bessoule F, Roberts PR, Morgan JM. Passive electrode effect reduces defibrillation threshold in bi-filament middle cardiac vein defibrillation. ACTA ACUST UNITED AC 2006; 8:113-7. [PMID: 16627420 DOI: 10.1093/europace/euj034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIMS To investigate whether a passive electrode effect decreases defibrillation threshold (DFT) in multi-filament middle cardiac vein (MCV) defibrillation. METHODS AND RESULTS Twelve pigs underwent active housing (AH) insertion, with defibrillation coils placed transvenously in right ventricular apex and superior vena cava. The MCV was cannulated, and 1.12F, 50 mm coil electrodes (Ela Medical SA, France) were deployed in its right and left branches. Lead placement was possible in 11 of 12 animals. DFT (J, mean +/- SD) was determined by three-reversal binary search and compared between the MCV monofilament (single filament deployed) and the AH (25.9 +/- 10.9) and the MCV mono + passive filaments (both filaments deployed, one connected) and the AH (19.9 +/- 11.4); 24% DFT reduction P = 0.008. CONCLUSION A bystander electrode adjacent to a monofilament electrode in the MCV reduces DFT by 24% when compared with monofilament MCV alone. Microfilament electrodes decrease DFT as auxiliary anode but not as sole anode.
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Affiliation(s)
- John R Paisey
- Wessex Cardiothoracic Centre, Southampton University Hospitals, UK.
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Paisey JR, Yue AM, Bessoule F, Allen S, Roberts PR, Morgan JM. Examination of a middle cardiac vein defibrillation coil as stand-alone anode, auxiliary anode, and bystander electrode in a transvenous defibrillation circuit. Pacing Clin Electrophysiol 2004; 27:1089-93. [PMID: 15305957 DOI: 10.1111/j.1540-8159.2004.00589.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In porcine studies anodes in the middle cardiac vein compare favorably with those in the RV. It has not been demonstrated whether the RV and middle cardiac vein or the middle cardiac vein alone anodes are superior when shocking to a conventional SVC and active housing cathode nor whether a bystander middle cardiac vein electrode exerts a passive electrode affect. Twelve pigs were anesthetized and had an active housing implanted in the left pectoral region and defibrillation coils placed at the RV apex and in the SVC. A custom-made defibrillation coil (Ela Medical) was advanced into the middle cardiac vein through a 9 Fr transvenous catheter. The DFT for three anodes (RV; RV and middle cardiac vein; middle cardiac vein) to the SVC and active housing was then assessed by a three reversal binary search, the order of testing was randomized. In seven animals DFT was assessed in the same way for the configuration of RV to SVC and active housing twice more, with and without a bystander middle cardiac vein coil electrode in place. The results were middle cardiac vein 7.5 +/- 1.7 J, RV and middle cardiac vein 7.3 +/- 1.7 J reduced DFT significantly compared to RV 13.8 +/- 4.2 J (both P < 0.000). There was no significant difference between the middle cardiac vein and the middle cardiac vein and RV (P = 0.67, 95% CI for difference -0.64-0.96). The DFT of RV to SVC and the active housing was the same with (13.2 +/- 4.0) and without (13.7 +/- 4.2) the middle cardiac vein bystander coil in place (P = 0.177, 95% CI for difference -0.33-1.33 J). Shocking to a SVC and active housing cathode, middle cardiac vein, and RV and middle cardiac vein anodes are equally effective in lowering DFT compared to the RV. The middle cardiac vein coil electrode does not exert a passive electrode affect on the RV to the SVC and active housing defibrillation.
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Affiliation(s)
- John R Paisey
- Wessex Cardiothoracic Center, Southampton, General Hospital, The United Kingdom.
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Dosdall DJ, Rothe DE, Brandon TA, Sweeney JD. Effect of Rapid Biphasic Shock Subpulse Switching on Ventricular Defibrillation Thresholds. J Cardiovasc Electrophysiol 2004; 15:802-8. [PMID: 15250866 DOI: 10.1046/j.1540-8167.2004.03652.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
INTRODUCTION The aim of this study was to demonstrate that significant reductions in defibrillation threshold (DFT) can be achieved by rapidly switching defibrillation pulses within an overall biphasic envelope between multiple endovascular electrode sets. METHODS AND RESULTS Defibrillation electrodes were implanted in four locations in nine anesthetized swine (41.7 +/- 8.7 kg). Electrodes were implanted into the right ventricular apex (RV), the superior vena cava (SVC), over the left pectoral region as a "hot can" (Can), and within the middle cardiac vein on the posterior left ventricular (LV) surface. The 50% DFT (level for which 50% of delivered shocks successfully defibrillated) for control shocks (7-ms first phase, 0.5-ms interpulse period, 4-ms second phase, RV- --> SVC+ + Can+) were determined to have energy of 20.5 +/- 5.5 J (mean +/- SD). Mean 50% DFTs were also determined for waveforms that split each phase of the same overall biphasic waveform between various electrode sets. Each phase was divided into 2, 3, 4, or 6 subpulses, the defibrillation shock was sequentially delivered to multiple electrode sets, and DFTs were determined (11.9 +/- 4.8 J, 11.7 +/- 2.9 J, 17.9 +/- 8.7 J, 16.7 +/- 6.1 J, respectively). DFT energy was statistically lower than the control (Wilcoxon sign rank test; P < 0.05) when each phase was divided into 2 or 3 subpulses. CONCLUSION Rapid shock switching within an overall biphasic waveform between electrode sets including an electrode in the middle cardiac vein potentially can lower DFT energy by 40% or more.
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Affiliation(s)
- Derek J Dosdall
- Harrington Department of Bioengineering, Arizona State University, Tempe, Arizona 85287-9709, USA
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Roberts PR, Zhang Y, Zhuan S, Mowrey KA, Wallick DW, Hills DG, Betts TR, Allen S, Ewert J, Mazgalev TN, Morgan JM. Single capacitive discharge utilizing an auxiliary shock in the coronary venous system reduces the defibrillation threshold. J Interv Card Electrophysiol 2001; 5:495-503. [PMID: 11752919 DOI: 10.1023/a:1013266600072] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
UNLABELLED Auxiliary shocks (AS) from electrodes sutured to the left ventricle (LV) prior to primary biphasic shocks (PS) have been shown to reduce defibrillation thresholds (DFT). Two capacitors are required to generate these waveforms. We investigate delivery of AS from one capacitor using a novel waveform. The epicardial surface of the LV is accessed transvenously via the middle cardiac vein (MCV) avoiding a thoracotomy. METHODS A defibrillation electrode was placed in the right ventricle (RV) and superior vena cava (SVC) in 12 pigs (37+/-2 kg). A 50x1.8 mm electrode was inserted in the MCV through a guide catheter. A can was placed in the left pectoral region. A monophasic AS (100 microF, 1.5 J) was delivered along one pathway before switching to deliver a biphasic waveform (40% tilt, 2 ms phase 2) along another. DFTs (PS+AS) were assessed using a binary search. Two configurations not incorporating AS acted as controls. DFTs were compared using repeated measures analysis of variance. RESULTS DFTs of the four novel configurations (AS/PS) were: RV-->Can/MCV-->Can=14.9+/-3.7 J, MCV-->Can/RV-->Can=17.2+/-5.7 J, RV-->SVC+Can/MCV-->SVC+Can=13.4+/-4.6 J, MCV-->SVC+Can/RV-->SVC+Can=17.1+/-5.9 J. Delivering AS in the RV followed by PS in the MCV reduced the DFT (RV-->Can (19.9+/-7.3 J, P<0.01) and RV-->SVC+Can (19.2+/-6.0 J, P<0.05)). CONCLUSIONS Delivering AS prior to PS in the MCV reduces the DFT by up to a third compared to conventional configurations of RV-->Can and RV-->SVC+Can. This is possible using only a single capacitor and an entirely transvenous approach to the LV.
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Affiliation(s)
- P R Roberts
- Wessex Cardiothoracic Center, Southampton General Hospital, United Kingdom.
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Meisel E, Pfeiffer D, Engelmann L, Tebbenjohanns J, Schubert B, Hahn S, Fleck E, Butter C. Investigation of coronary venous anatomy by retrograde venography in patients with malignant ventricular tachycardia. Circulation 2001; 104:442-7. [PMID: 11468207 DOI: 10.1161/hc2901.093145] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND The coronary venous system is increasingly used for left ventricular or biventricular pacing in patients with severe heart failure. The present study investigated the structure of the coronary veins in patients presenting with structural heart disease and malignant ventricular tachyarrhythmias. The availability of veins for possible lead placement was assessed. METHODS AND RESULTS The number, relative size, and location of coronary veins were evaluated by retrograde venography in 129 patients undergoing cardioverter-defibrillator implantation. Detailed x-ray image analysis was performed in 86 patients, for whom optimal coronary sinus occlusion and vein visualization was achieved. The anterior interventricular vein and the middle cardiac vein were visible in 85 (99%) of 86 patients and in 86 (100%) of 86 patients, respectively. Between these 2 veins, at least 1 additional prominent vein was visible in 85 (99%) of 86 patients. Just 1 vein was present in 44 (51%) of 86 patients. Two veins were observed in 40 (46%) of 86 patients, and >2 veins were visualized in 2 (2%) of 86 patients. Venous anatomy allowed positioning of a 0.014-in guidewire in a coronary vein in 115 (93%) of 124 patients. CONCLUSIONS The presence, diameter, angulation, and tortuosity of veins as visualized by retrograde venography determine their acceptability for the placement of a lead in a predetermined location. Despite the considerable variability of the coronary venous system among patients, a lateral vessel for lead introduction was available in 82%, and a posterior or lateral vessel was available in 99% of individuals within a patient population that could potentially benefit from a lead on the left ventricle.
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Affiliation(s)
- E Meisel
- Heart and Circulation Center, Dresden, Germany.
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