Publications
Below you can find a list of our published research.
Below you can find a list of our published research.
251 results
Cited 16 times since 2004 (0.8 per year) source: EuropePMC
Critical care medicine, Volume 32, Issue 4, 1 1 2004, Pages 1087-1089 Right ventricular function and failure: methods, models, and mechanisms. Steendijk P
Cited 2 times since 2004 (0.1 per year) source: EuropePMC
Physiological measurement, Volume 25, Issue 2, 1 1 2004, Pages 565-576 Assessment of parallel conductance for the trans-cardiac conductance method: can we use the hypertonic saline method with pulmonary artery injections? Staal EM, Baan J, Jukema JW, van der Wall EE, Steendijk P
The trans-cardiac conductance (TCC) method provides on-line left ventricular (LV) volume signals by determining the electrical conductance of blood in the LV using central venous and epithoracic electrodes. Conductive structures outside the LV cause a 'parallel conductance' offset term (Vp) that is determined by bolus injections of hypertonic saline in the pulmonary artery (Vp(saline)). Analysis of the increased conductance signal during passage of the bolus through the LV yields Vp(sa... Abstract
Cited 114 times since 2004 (5.7 per year) source: EuropePMC
Pacing and clinical electrophysiology : PACE, Volume 27, Issue 3, 1 1 2004, Pages 308-313 QRS duration and shortening to predict clinical response to cardiac resynchronization therapy in patients with end-stage heart failure. Molhoek SG, VAN Erven L, Bootsma M, Steendijk P, Van Der Wall EE, Schalij MJ
Despite current selection criteria (NYHA Class III-IV, LVEF < 35%, QRS > 120 ms with LBBB), 30% of patients do not benefit from cardiac resynchronization therapy (CRT). The use of QRS duration as selection criteria for CRT has not been evaluated systematically yet. Accordingly, the value of QRS duration at baseline (and reduction in QRS duration after CRT) to predict responders was studied. Patients were evaluated at baseline and after 6 months of CRT for NYHA Class, quality of life score,... Abstract
Cited 5 times since 2004 (0.2 per year) source: EuropePMC
Clinical science (London, England : 1979), Volume 106, Issue 2, 1 1 2004, Pages 173-181 Dobutamine induces ineffective work in regional ischaemic myocardium: an experimental strain rate imaging study. Weidemann F, Broscheit J, Eberbach N, Steendijk P, Voelker W, Greim C, Ertl G, Roewer N, Strotmann JM
In the present study, we sought to investigate the effects of differing inotropic conditions on regional myocardial function in ischaemic segments. In an experimental pig model ( n =11), the regional deformation parameters peak systolic strain rate [SR(SYS) (peak velocity of thickening)], systolic strain [epsilon(SYS) (systolic wall thickening)] and post-systolic strain [epsilon(PST) (ongoing wall thickening after end of systole)] were measured during normal perfusion and regional ischaemia of t... Abstract
Cited 20 times since 2004 (1 per year) source: EuropePMC
Heart (British Cardiac Society), Volume 90, Issue 1, 1 1 2004, Pages 97-98 Atrial and brain natriuretic peptides as markers of response to resynchronisation therapy. Molhoek SG, Bax JJ, van Erven L, Bootsma M, Steendijk P, Lentjes E, Boersma E, van der Laarse A, van der Wall EE, Schalij MJ
Cited 287 times since 2003 (14 per year) source: EuropePMC
The American journal of cardiology, Volume 92, Issue 10, 1 1 2003, Pages 1238-1240 Left ventricular dyssynchrony predicts benefit of cardiac resynchronization therapy in patients with end-stage heart failure before pacemaker implantation. Bax JJ, Marwick TH, Molhoek SG, Bleeker GB, van Erven L, Boersma E, Steendijk P, van der Wall EE, Schalij MJ
We evaluated patients with end-stage heart failure who have a high likelihood of response to cardiac resynchronization therapy (biventricular pacing). It appears that 20% of patients do not respond to this expensive therapy despite the use of selection criteria (dilated cardiomyopathy, heart failure, New York Heart Association class II or IV, left ventricular ejection fraction 120 ms). The presence of left ventricular dyssynchrony is needed to result in improvement after cardiac resynchronizatio... Abstract
Cited 44 times since 2003 (2.1 per year) source: EuropePMC
American journal of physiology. Heart and circulatory physiology, Volume 286, Issue 2, 9 2 2003, Pages H723-30 Quantification of left ventricular mechanical dyssynchrony by conductance catheter in heart failure patients. Steendijk P, Tulner SA, Schreuder JJ, Bax JJ, van Erven L, van der Wall EE, Dion RA, Schalij MJ, Baan J
Mechanical dyssynchrony is an important codeterminant of cardiac dysfunction in heart failure. Treatment, either medical, surgical, or by pacing, may improve cardiac function partly by improving mechanical synchrony. Consequently, the quantification of ventricular mechanical (dys)synchrony may have important diagnostic and prognostic value and may help to determine optimal therapy. Therefore, we introduced new indexes to quantify temporal and spatial aspects of mechanical dyssynchrony derived fr... Abstract
Cited 25 times since 2003 (1.2 per year) source: EuropePMC
Radiology, Volume 229, Issue 2, 2 1 2003, Pages 513-519 Real-time MR imaging of aortic flow: influence of breathing on left ventricular stroke volume in chronic obstructive pulmonary disease. van den Hout RJ, Lamb HJ, van den Aardweg JG, Schot R, Steendijk P, van der Wall EE, Bax JJ, de Roos A
Purpose: To assess real-time changes of left ventricular stroke volume (SV) in relation to the breathing pattern in healthy subjects and in patients with chronic obstructive pulmonary disease (COPD). Materials and methods: Real-time magnetic resonance (MR) imaging flow measurements were performed in the ascending aorta of 10 healthy volunteers and nine patients with severe COPD. Breathing maneuvers were registered with an abdominal pressure belt, which was synchronized to the electrocardiographi... Abstract
Cited 20 times since 2003 (1 per year) source: EuropePMC
Anesthesia and analgesia, Volume 97, Issue 4, 1 1 2003, Pages 950-957 Perioperative assessment of left ventricular function by pressure-volume loops using the conductance catheter method. Tulner SAF, Klautz RJM, van Rijk-Zwikker GL, Engbers FHM, Bax JJ, Baan J, van der Wall EE, Dion RA, Steendijk P
Unlabelled: Interpretation of perioperative measurements of cardiac function during cardiac surgery is complicated by changes in loading conditions induced by anesthesia, cardiopulmonary bypass (CPB), and the surgical procedure itself. Quantification of left ventricular (LV) function by pressure-volume relations as obtained by the conductance catheter would be advantageous because load-independent indices can be determined. Accordingly, we evaluated methodological aspects of the conductance-cath... Abstract
Cited 4 times since 2003 (0.2 per year) source: EuropePMC
The international journal of cardiovascular imaging, Volume 19, Issue 4, 1 1 2003, Pages 259-266 End-diastolic and end-systolic volume from the left ventricular angiogram: how accurate is visual frame selection? Comparison between visual and semi-automated comnputer-assisted analysis. Staal EM, de Heer M, Jukema JW, Koning G, van der Wall EE, Reiber JH, Baan J, Steendijk P
Background: End-diastolic (ED), end-systolic (ES) left ventricular (LV) volumes and LV ejection fraction (LVEF) are important parameters for clinical decision making in heart disease. In clinical practice the frames from cine-angiography with the largest and smallest opacified LV areas are visually selected and the endocardial borders traced as LVED and LVES contours, respectively. We compared the accuracy of this visual method using two frames with a semi-automated computer assisted frame-by-fr... Abstract
Cited 4 times since 2003 (0.2 per year) source: EuropePMC
European journal of heart failure, Volume 5, Issue 3, 1 1 2003, Pages 315-317 Eligibility for biventricular pacing in patients with an implantable cardioverter defibrillator. Molhoek SG, Bax JJ, van Erven L, Steendijk P, van der Wall EE, Schalij MJ
Implantable cardioverter defibrillator (ICD)-therapy prevents sudden death in patients at high risk, but incidence of death due to heart failure remains unaltered. Recent data suggest that biventricular (BV) pacing is useful in patients with heart failure. It is unclear, how many patients with an ICD indication may have an indication for BV pacing. Therefore all patients who received an ICD were analyzed for eligibility of BV pacing using the following criteria: NYHA class III or IV, QRS duratio... Abstract
Netherlands heart journal : monthly journal of the Netherlands Society of Cardiology and the Netherlands Heart Foundation, Volume 11, Issue 5, 1 1 2003, Pages 203-209 Simultaneous measurement of right and left ventricular volume by the conductance catheter technique in the newborn lamb. Cardozo RH, de Vroomen M, van Bel F, Baan J, Steendijk P
Background: Measurement of absolute ventricular volume with the conductance catheter technique has been documented extensively for the left ventricle (LV). More recently, the same technique has been applied in studies of right ventricular (RV) performance. In the present study we performed simultaneous measurements of LV and RV volumes. Conversion of measured conductances to absolute volumes requires the assessment of slope factor alpha (α) and parallel conductance correction volume (Vc) for bot... Abstract
Cited 7 times since 2003 (0.3 per year) source: EuropePMC
The Journal of thoracic and cardiovascular surgery, Volume 125, Issue 3, 1 1 2003, Pages 481-490 Effects of acute left ventricular unloading on right ventricular function in normal and chronic right ventricular pressure-overloaded lambs. Leeuwenburgh BP, Helbing WA, Steendijk P, Schoof PH, Baan J
Objective: Right ventricular pressure overload occurs in several types of (congenital) heart disease, as well as in pulmonary disease. Clinical outcome in some of these patient groups might in part be related to left ventricular loading conditions. The effects of left ventricular unloading on the function of the hypertrophic right ventricle have not been studied. We aimed to study the effects of left ventricular unloading on right ventricular hemodynamics and contractility in an animal model of... Abstract
Cited 6 times since 2003 (0.3 per year) source: EuropePMC
IEEE transactions on bio-medical engineering, Volume 50, Issue 2, 1 1 2003, Pages 234-240 The trans-cardiac conductance method for on-line measurement of left ventricular volume: assessment of parallel conductance offset volume. Staal EM, Steendijk P, Baan J
The trans-cardiac conductance (TCC) method provides on-line left ventricular (LV) volume signals by determining the electrical conductance of blood in the LV by means of central venous and epithoracic electrodes. Conductive structures outside the LV blood pool cause a "parallel conductance" offset term (Vp) that can be determined by bolus injections of hypertonic saline in the pulmonary artery (Vp(saline)), which cause a transient increase in blood conductivity. This study in anestheti... Abstract
Cited 14 times since 2003 (0.7 per year) source: EuropePMC
The Journal of thoracic and cardiovascular surgery, Volume 125, Issue 2, 1 1 2003, Pages 231-237 Chronic and adjustable pulmonary artery banding. Leeuwenburgh BP, Schoof PH, Steendijk P, Baan J, Mooi WJ, Helbing WA
Objective: Banding of the pulmonary artery might be required to prevent pulmonary vascular damage in patients with increased pulmonary artery flow and to retrain the left ventricle in preparation for an arterial switch operation in patients with congenitally corrected transposition of the great arteries. Readjustment of the pulmonary artery band might be required in the postoperative period. In this study we aimed to test the feasibility of a novel device for bidirectionally adjustable pulmonary... Abstract
Cited 136 times since 2003 (6.4 per year) source: EuropePMC
The American journal of cardiology, Volume 91, Issue 1, 1 1 2003, Pages 94-97 Usefulness of myocardial tissue Doppler echocardiography to evaluate left ventricular dyssynchrony before and after biventricular pacing in patients with idiopathic dilated cardiomyopathy. Bax JJ, Molhoek SG, van Erven L, Voogd PJ, Somer S, Boersma E, Steendijk P, Schalij MJ, Van der Wall EE
Cited 29 times since 2002 (1.3 per year) source: EuropePMC
American journal of physiology. Heart and circulatory physiology, Volume 284, Issue 1, 12 2 2002, Pages H350-7 Impact of pericardial restraint on right atrial mechanics during acute right ventricular pressure load. Maniar HS, Prasad SM, Gaynor SL, Chu CM, Steendijk P, Moon MR
Optimization of right atrial (RA) mechanics is important for maintaining right ventricular (RV) filling and global cardiac output. However, the impact of pericardial restraint on RA function and the compensatory role of the right atrium to changes in RV afterload remain poorly characterized. In eight open-chest sheep, RA elastance (contractility) and chamber stiffness were measured (RA pressure-volume relations) at baseline and during partial pulmonary artery (PA) occlusion. Data were collected... Abstract
Cited 42 times since 2002 (1.9 per year) source: EuropePMC
The American journal of cardiology, Volume 90, Issue 4, 1 1 2002, Pages 379-383 Effectiveness of resynchronization therapy in patients with end-stage heart failure. Molhoek SG, Bax JJ, van Erven L, Bootsma M, Boersma E, Steendijk P, van der Wall EE, Schalij MJ
Biventricular pacing has been introduced to treat patients with end-stage heart failure, and short-term results of this technique are promising. Because data on longer follow-up are limited to 3-month follow-up, the sustained effect of biventricular pacing is unclear and long-term survival is unknown. Forty patients with end-stage heart failure in New York Heart Association (NYHA) functional class III or IV with left ventricular (LV) ejection fraction (EF) 120 ms, and left bundle branch block mo... Abstract
Cited 6 times since 2002 (0.3 per year) source: EuropePMC
Critical care medicine, Volume 30, Issue 6, 1 1 2002, Pages 1301-1305 Continuous on-line measurement of absolute left ventricular volume by transcardiac conductance: angiographic validation in sheep. Staal EM, Steendijk P, Koning G, Dijkstra J, Jukema JW, Baan J
Objective: Validation of the transcardiac conductance method for continuous, on-line measurement of absolute left ventricular volume by comparison with biplane angiography. Design: Controlled, prospective animal study. Setting: Catheterization laboratory of the Leiden University Medical Center. Subjects: Six anesthetized sheep. Interventions: Subjects were studied at baseline, during infusion of dobutamine, and during volume loading and beta blockade. In a pilot experiment, a coronary artery was... Abstract
Cited 70 times since 2002 (3.2 per year) source: EuropePMC
American journal of physiology. Heart and circulatory physiology, Volume 282, Issue 4, 1 1 2002, Pages H1350-8 Indexes of diastolic RV function: load dependence and changes after chronic RV pressure overload in lambs. Leeuwenburgh BP, Steendijk P, Helbing WA, Baan J
Diastolic function is a major determinant of ventricular performance, especially when loading conditions are altered. We evaluated biventricular diastolic function in lambs and studied possible load dependence of diastolic parameters [minimum first derivative of pressure vs. time (dP/dt(min)) and time constant of isovolumic relaxation (tau)] in normal (n = 5) and chronic right ventricular (RV) pressure-overloaded (n = 5) hearts by using an adjustable band on the pulmonary artery (PAB). Pressure-... Abstract