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Biomedical subjects

Hubert W Vliegen

Publications and source records attributed to Hubert W Vliegen.

At least 37 records · Page 2Linked to original sources
PubMed2005

Disparity between dobutamine stress and physical exercise magnetic resonance imaging in patients with an intra-atrial correction for transposition of the great arteries.

BACKGROUND: In patients with an intra-atrial correction for transposition of the great arteries (TGA) an abnormal response to stress testing is common. However, hemodynamic responses may vary substantially when different stress tests are used. We compared the hemodynamic response to dobutamine stress with the response to physical exercise in patients and controls. METHODS: Thirty-nine patients and 25 age/sex-matched control subjects underwent either dobutamine stress (15 microg/kg/min) or submaximal physical exercise cardiovascular magnetic resonance. End-systolic and end-diastolic right ventricular volumes (ESV; EDV) were determined. Five representative patients underwent both stress tests. For these patients, wall thickening reserve was calculated as systolic wall thickening during stress minus systolic wall thickening at rest. RESULTS: In controls, dobutamine stress and physical exercise showed similar responses: stroke volume, cardiac output, and ejection fraction increased significantly, whereas ESV decreased significantly and EDV was unchanged. In patients, stroke volume did not increase with either dobutamine or exercise (-8.6% vs. 2.9%). Ejection fraction increased significantly with dobutamine (16%, p < 0.001) but tended to decrease during exercise (-2.1%, P = NS). EDV and ESV decreased during dobutamine but were unchanged during exercise. (-22% vs. 5.0%, P < 0.001; -36% vs. 9.0%, P < 0.01 respectively). Wall thickening reserve was higher with dobutamine than with exercise (0.9 mm vs. -0.6 mm, P = 0.02). CONCLUSION: Dobutamine stress and physical exercise cannot be used interchangeably for assessment of systolic and diastolic function in patients with an intra-atrial correction for TGA. This may have consequences for the use of different stress CMR approaches in the clinical setting.

Adult↗
PubMed2005

Evaluation of saphenous vein coronary artery bypass graft flow by cardiovascular magnetic resonance.

Cardiovascular magnetic resonance (CMR) with flow velocity mapping has emerged as a noninvasive method to measure flow in saphenous vein coronary artery bypass grafts. The aim of the current study was to retrospectively test two previously described analysis methods on a large CMR data set and to compare their diagnostic accuracy in detecting diseased vein grafts. In 125 vein grafts of 68 patients, volume flow parameters (volume flow, systolic and diastolic peak flow, diastolic-to-systolic flow ratio at rest and during adenosine stress, and flow reserve) were derived from the velocity maps. Method 1 implemented basal flow < 20 ml/min or flow reserve < 2, yielding a sensitivity and specificity of 70% and 38% in the detection of a diseased graft or recipient vessel. Method 2 used receiver operating characteristic (ROC) curve analysis and implemented all significant volume flow parameters in a logistic regression model, yielding a sensitivity of 74% with a specificity of 68% in the detection of a diseased graft or recipient vessel. Evaluating single and sequential grafts separately, this method yielded a sensitivity and specificity of 79% and 87% for single grafts, and 62% and 94% for sequential grafts in the detection of > or = 50% stenosis in grafts or recipient vessels. Cut-off values were formulated for the respective volume flow parameters, which maximally separate grafts with and without > or = 50% stenosis. Using ROC curve analysis with logistic regression the specificity of the analysis method improved considerably. For the current data set the best results were acquired when single and sequential grafts were separately analyzed.

Aged↗
PubMed2005

Corrected tetralogy of Fallot: delayed enhancement in right ventricular outflow tract.

PURPOSE: To evaluate retrospectively the presence of fibrosis and largest diameter of the right ventricular outflow tract (RVOT) by using delayed enhancement magnetic resonance (MR) imaging in patients who had undergone initial correction for tetralogy of Fallot. MATERIALS AND METHODS: MR imaging was performed in 24 consecutive patients (16 male, eight female; mean age, 25 years; age range, 13-47 years) with corrected tetralogy of Fallot. The study protocol was approved by the local ethics committee, and informed consent was not required. Fifteen minutes after injection of 0.2 mmol/kg gadopentetate dimeglumine, an inversion-recovery turbo field-echo sequence was applied for detection of delayed enhancement. Right ventricular volumes, ejection fraction, and anterior-posterior diameter of the RVOT were calculated. Mann-Whitney nonparametric testing was used to compare measurements of ventricular volume, function, and anterior-posterior diameter of the RVOT in the presence or absence of delayed enhancement. Correlation was tested with Pearson coefficient. RESULTS: Delayed enhancement was seen in 17 patients in the RVOT. During initial surgery, transannular patching was performed in 13 (76%) of 17 patients, RVOT patching in one (6%) of 17 patients, and the Brock procedure in two (12%) of 17 patients. In one patient, the type of initial RVOT repair was unknown. Patients with delayed enhancement in the RVOT, as compared with those without delayed enhancement in the RVOT, had increased RVOT diameter (32 mm +/- 7 [standard deviation] vs 22 mm +/- 3, P < .01), decreased right ventricular ejection fraction (43% +/- 6.3 vs 54% +/- 10, P < .001), and increased end-diastolic volume (175 mL/m2 +/- 42 vs 118 mL/m2 +/- 34, P < .01). The diameter of the RVOT correlated with increased right ventricular end-systolic volume (R = 0.86) and was inversely related to ejection fraction (R = -0.65). CONCLUSION: Delayed enhancement occurs frequently in patients after correction for tetralogy of Fallot. Delayed enhancement in the RVOT was associated with RVOT dilatation, which adversely affects right ventricular hemodynamics.

Adolescent↗
PubMed2004

Noninvasive evaluation of the coronary arteries with multislice computed tomography in hypertensive patients.

Because patients with hypertension are at increased risk for coronary artery disease, early and noninvasive identification of the disease in patients with hypertension is important. Recently, multislice computed tomography (MSCT) has been demonstrated to allow both noninvasive coronary angiography and assessment of left ventricular function. The purpose of the present study therefore was to demonstrate the feasibility of this approach in patients with hypertension with known or suspected coronary artery disease and to compare the results to invasive coronary angiography and 2-dimensional echocardiography, respectively. MSCT was performed in 31 patients with confirmed hypertension. From the MSCT images, the presence of significant coronary stenoses (>or=50% luminal narrowing) and regional wall motion abnormalities were evaluated and compared with invasive coronary angiography and 2-dimensional echocardiography. In addition, left ventricular ejection fraction was calculated from the MSCT images. A total of 243 (88%) coronary artery segments could be evaluated with MSCT. Sensitivity and specificity for the detection of significant coronary artery stenoses were 93% and 96%. On a per-patient basis, MSCT was accurate in 28 (90%) patients. Mean left ventricular ejection fraction was 46+/-14% (range, 16% to 64%). The agreement for assessing regional wall motion was 91% (kappa statistic, 0.81). In conclusion, simultaneous, noninvasive evaluation of coronary artery stenoses and left ventricular function with MSCT is accurate in patients with hypertension. This noninvasive approach may allow triage of patient treatment in terms of conservative versus invasive management.

Aged↗
PubMed2004

Functional significance of stenoses in coronary artery bypass grafts. Evaluation by single-photon emission computed tomography perfusion imaging, cardiovascular magnetic resonance, and angiography.

OBJECTIVES: This study was designed to perform a head-to-head comparison between single-photon emission computed tomography (SPECT) and cardiovascular magnetic resonance (CMR) to evaluate hemodynamic significance of angiographic findings in bypass grafts. BACKGROUND: The hemodynamic significance of a bypass graft stenosis may not always accurately be determined from the coronary angiogram. A variety of diagnostic tests (invasive or noninvasive) can further characterize the hemodynamic consequence of a lesion. METHODS: Fifty-seven arterial and vein grafts in 25 patients were evaluated by angiography, SPECT perfusion imaging, and coronary flow velocity reserve determination by CMR. Based on angiography and SPECT, four different groups could be identified: 1) no significant stenosis (<50%), normal perfusion; 2) significant stenosis (>/=50%), abnormal perfusion; 3) significant stenosis, normal perfusion (no hemodynamic significance); and 4) no significant stenosis, abnormal perfusion (suggesting microvascular disease). RESULTS: A complete evaluation was obtained in 46 grafts. Single-photon emission computed tomography and CMR provided similar information in 37 of 46 grafts (80%), illustrating good agreement (kappa = 0.61, p < 0.001). Eight grafts perfused a territory with scar tissue. When agreement between SPECT and CMR was restricted to grafts without scar tissue, it improved to 84% (kappa = 0.68). Integration of angiography with SPECT categorized 14 lesions in group 1, 23 in group 2, 6 in group 3, and 3 in group 4. Single-photon emission computed tomography and CMR agreement per group was 86%, 78%, 100%, and 33%, respectively. CONCLUSIONS: Head-to-head comparison showed good agreement between SPECT and CMR for functional evaluation of bypass grafts. Cardiovascular magnetic resonance may offer an alternative method to SPECT for functional characterization of angiographic lesions.

Aged↗
PubMed2004

Feasibility of assessment of coronary stent patency using 16-slice computed tomography.

Intracoronary stent implantation is a frequently performed procedure in the treatment of stenoses in coronary arteries, but in-stent restenosis occurs in approximately 10% to 15% of patients. A noninvasive diagnostic procedure to evaluate in-stent restenosis would therefore be of great benefit. We investigated the feasibility of assessing stent patency with 16-slice computed tomography. Multislice computed tomography (MSCT) was performed in 22 patients with previously implanted stents. For each stent, assessability was determined and related to stent type and diameter. Subsequently, the presence of significant restenosis was determined in the evaluable stents. In addition, peristent lumina (5 mm proximal and distal to the stent) were evaluated. Conventional angiography in combination with quantitative coronary angiography served as the standard of reference. MSCT was performed successfully in all but 1 patient. Of 65 stents, 50 (77%) were determined assessable. Uninterpretable stents tended to have a thicker strut and/or a smaller diameter. In the evaluable stents, 7 of 9 stenoses were detected and the absence of restenosis was correctly identified in all 41 patent stents, resulting in a sensitivity and specificity of 78% and 100%, respectively. Sensitivity and specificity for the detection of peristent stenosis were 75% and 96%, respectively. In conclusion, MSCT may be useful in the assessment of stent patency and may function as a gatekeeper before invasive diagnostic procedures.

Aged↗
PubMed2004

Blood flow in coronary artery bypass vein grafts: volume versus velocity at cardiovascular MR imaging.

Forty-nine patients with previous bypass surgery underwent coronary angiography and cardiovascular magnetic resonance (MR) imaging of single-vein bypass grafts. Volume flow and velocity analyses were performed and compared on MR velocity maps. Bland-Altman analysis showed close agreement between the two types of analysis. Comparison of areas under the receiver operating characteristic curve revealed no significant differences between the analyses for detection of stenoses of 70% or greater. Diagnostic accuracy for volume flow and velocity parameters was 92% and 93%, respectively. Velocity analysis appears to be the preferred method, because it is less time-consuming and has a similar diagnostic accuracy to volume flow analysis.

Adult↗
PubMed2004

Six-months of recombinant human GH therapy in patients with ischemic cardiac failure.

Growth hormone therapy in patients with idiopathic dilated cardiomyopathy and ischemic cardiac failure has revealed varying effects on systolic function, probably related to the response in serum insulin-like growth factor I (IGF-I) levels. As diastolic function has not been studied thoroughly, we studied the effects of 6 months of recombinant human growth hormone (rh GH) treatment on systolic and diastolic function in patients with ischemic cardiac failure, using cardiovascular magnetic resonance (MR) imaging. Nineteen patients with ischemic cardiac failure (left ventricular ejection fraction (LVEF), <40%) were studied in a randomized trial. Nine patients received 6 months treatment with growth hormone (2 IU/day). Systolic and diastolic function were assessed at baseline and after 26 weeks by cardiovascular MR imaging. No differences were found in systolic and diastolic function between rh GH treated patients and controls. No change was observed in left ventricular mass index (LVMI), end-diastolic volume, end-systolic-volume and ejection fraction. The treated patients showed no clinical improvement. Six months of treatment with growth hormone therapy in ischemic cardiac failure has no favorable effects on LVMI, on systolic and diastolic function.

Aged↗
PubMed2004

Relation between exercise-induced hypertension and sustained hypertension in adult patients after successful repair of aortic coarctation.

OBJECTIVES: To investigate whether exercise-induced hypertension in successfully repaired adult post-coarctectomy patients is associated with hypertension on 24-h blood pressure measurement and increased left ventricular mass. METHODS: One hundred and forty-four consecutive post-coarctectomy patients (mean age 31.5 years, range 17-74 years; mean age at repair 7.9 years, range 0-45 years) from three tertiary referral centres were studied using ambulatory blood pressure monitoring, treadmill exercise testing and echocardiography. RESULTS: Of the 144 patients, 27 (19%) were known to have sustained hypertension, based on their history, and all were on antihypertensive medication. However, 32 (27%) of the remaining 117 patients showed elevated mean daytime systolic blood pressure readings at 24-h ambulatory blood pressure monitoring (systolic blood pressure > or = 140 mmHg). Of the remaining 85 patients with normal mean daytime systolic blood pressure, 18 patients (21%) had exercise-induced hypertension (maximal exercise systolic blood pressure > 200 mmHg). Mean daytime systolic blood pressure was higher in the exercise-induced hypertensive patients compared to the normotensive patients with normal exercise blood pressure (134 +/- 5 versus 129 +/- 7 mmHg, P = 0.008). By multivariate analysis, both maximal exercise systolic blood pressure (P = 0.007) and resting systolic blood pressure (P < 0.0001) were independently associated with mean daytime systolic blood pressure. Maximal exercise systolic blood pressure had no independent predictive value for left ventricular mass (P = 0.132). CONCLUSIONS: In adult post-coarctectomy patients, maximal exercise systolic blood pressure is independently associated with mean daytime systolic blood pressure at ambulatory blood pressure monitoring. In this study no independent predictive value of maximal exercise systolic blood pressure for left ventricular mass could be demonstrated.

Adult↗
PubMed2004

Right ventricular function after pulmonary valve replacement in patients with tetralogy of Fallot.

PURPOSE: To assess the time course of right ventricular (RV) function improvement after pulmonary valve replacement (PVR) in patients 25.2 years +/- 7.0 after repair of tetralogy of Fallot. MATERIALS AND METHODS: The medical ethics committee approved this study, and informed consent was obtained. Cardiac magnetic resonance (MR) imaging was performed before, 7 months after, and 19 months after PVR in 25 consecutive patients with tetralogy of Fallot with a 1.5-T MR imager. RV function was assessed with gradient-echo sequences in the short-axis plane. Pulmonary flow was assessed with a velocity-encoded phase-contrast sequence. Paired t test was used to evaluate follow-up data. Independent samples t test was used to assess differences based on the presence of recurrent pulmonary regurgitation (PR). RESULTS: Mean indexed RV end-diastolic volume decreased from 166.9 mL/m(2) +/- 41.3 before PVR to 113.5 mL/m(2)+/- 35.7 (P < .001) at 7-month follow-up and 111.7 mL/m(2)+/- 41.1 (P = .46) at 19-month follow-up. The RV ejection fraction was corrected for PR and improved from 25.0% +/- 7.7 before surgery to 44.1% +/- 11.9 (P < .001) and 45.2% +/- 11.1 (P = .39), at 7- and 19-month follow-up, respectively. Recurrent PR after PVR was found in 11 patients; 14 patients did not have recurrent PR. Total reduction of indexed RV end-diastolic volume at 19 months follow-up was more prominent in patients who did not have recurrent PR than in patients who did have recurrent PR (P < .05). Furthermore, improvement of RV ejection fraction corrected for regurgitation was more marked in patients who did not have recurrent PR than in patients who did have recurrent PR (P < .05). CONCLUSION: In patients with tetralogy of Fallot, RV function improves rapidly after PVR and is sustained at 19-month follow-up in most patients; however, recurrence of PR after PVR appears to reduce recovery of RV systolic function.

Adolescent↗
PubMed2004

Noninvasive angiography and assessment of left ventricular function using multislice computed tomography in patients with type 2 diabetes.

OBJECTIVE: Early identification of coronary artery disease (CAD) in patients with diabetes is important because these patients are at increased risk for CAD and have worse outcome than nondiabetic patients after CAD is diagnosed. Recently, noninvasive coronary angiography and assessment of left ventricular function has been demonstrated with multislice computed tomography (MSCT). The purpose of the present study was to validate this approach in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: MSCT was performed in 30 patients with confirmed type 2 diabetes. From the MSCT images, coronary artery stenoses (> or =50% luminal narrowing) and left ventricular function (left ventricular ejection fraction, regional wall motion) were evaluated and compared with results of conventional angiography and two-dimensional echocardiography. RESULTS: Two hundred twenty of 256 coronary artery segments (86%) were interpretable with MSCT. In these segments, sensitivity and specificity for detection of coronary artery stenoses were 95%. Including the uninterpretable segments, sensitivity and specificity were 81 and 82%, respectively. Bland-Altman analysis in the comparison of left ventricular ejection fractions demonstrated a mean difference of -0.48 +/- 3.8% for MSCT and echocardiography, which was not significantly different from 0. Agreement between the two modalities for assessment of regional contractile function was excellent (91%, kappa statistic 0.81). CONCLUSIONS: Accurate noninvasive evaluation of both the coronary arteries and left ventricular function with MSCT is feasible in patients with type 2 diabetes. This noninvasive approach may allow optimal identification of high-risk patients.

Coronary Disease↗
PubMed2003

Value of magnetic resonance imaging for the noninvasive detection of stenosis in coronary artery bypass grafts and recipient coronary arteries.

BACKGROUND: Magnetic resonance imaging (MRI) is a potential noninvasive diagnostic tool to detect coronary artery bypass graft stenosis, but its value in clinical practice remains to be established. We investigated the value of MRI in detecting stenotic grafts, including recipient vessels. METHODS AND RESULTS: We screened for inclusion 173 consecutive patients who were scheduled for coronary angiography because of recurrent chest pain after coronary artery bypass grafting (CABG). We studied 69 eligible patients with 166 grafts (81 single vein, 44 sequential vein, and 41 arterial grafts). MRI with baseline and stress flow mapping was performed. Both scans were successful in 80% of grafts. Grafts were divided into groups with stenosis > or =50% (n=72) and > or =70% (n=48) in the graft or recipient vessels. Marginal logistic regression was used to predict the probability for the presence of stenosis per graft type using multiple MRI variables. Receiver operator characteristics (ROC) analysis was performed to assess the diagnostic value of MRI. Sensitivity (95% confidence interval)/specificity (95% confidence interval) in detecting single vein grafts with stenosis > or =50% and > or =70% were 94% (86 to 100)/63% (48 to 79) and 96% (87 to 100)/92% (84 to 100), respectively. CONCLUSIONS: MRI with flow mapping is useful for identifying grafts and recipient vessels with flow-limiting stenosis. Flow scans could be obtained in 80% of the grafts. This proof-of-concept study suggests that noninvasive MRI detection of stenotic grafts in patients who present with recurrent chest pain after CABG may be useful in selecting those in need of an invasive procedure.

Adenosine↗
PubMed2003

Evaluation of ECG criteria for left ventricular hypertrophy before and after aortic valve replacement using magnetic resonance imaging.

PURPOSE: Evaluation of different electrocardiographic criteria for left ventricular hypertrophy (ECG-LVH criteria) using left ventricular mass index (LVMI) determined by magnetic resonance imaging (MRI). In addition, the relation between LVMI regression after aortic valve replacement and corresponding ECG changes regarding LVH was studied. METHODS: A group of 31 patients with severe aortic valve disease was studied to assess the presence of ECG-LVH and to measure LVMI and LV end-diastolic volume index (LVEDVI); 13 patients were restudied at 9.8 +/- 2.7 months after aortic valve replacement. RESULTS: Three criteria had a sensitivity of 100% (SV1 + RV5 or RV6 > 3.0 mV; SV1 or SV2 + RV5 > or = 3.5 mV; SV1 or SV2 + RV5 or RV6 > 3.5 mV), at the cost of specificity (50%, 44.4% and 44.4%, respectively). The R in I > 1.4 mV had a specificity of 100%, at the cost of both sensitivity and accuracy (13.6% and 54.5%, respectively). The Romhilt-Estes point score system, using > or = 4 points as cut-off value for LVH, provided the overall best accuracy of 79.5%. The number of Romhilt-Estes points also showed the best correlation with LVMI, both before and after aortic valve replacement (r = 0.81 and r = 0.67, respectively). CONCLUSIONS: Substantial differences in sensitivity, specificity, accuracy, and correlation with LVMI were found among several ECG-LVH criteria. No single criterion performed optimally since the highest sensitivity, specificity, accuracy, and correlation with LVMI were found with different criteria. The present study may therefore contribute to a more targeted use of the existing ECG-LVH criteria.

Aortic Valve Insufficiency↗
PubMed2003

Vein graft function improvement after percutaneous intervention: evaluation with MR flow mapping.

PURPOSE: To provide functional reference values in single and sequential vein grafts by using magnetic resonance (MR) flow mapping and to examine the effect of percutaneous intervention (PCI) on coronary artery bypass graft function. MATERIALS AND METHODS: Fast MR flow mapping at baseline and during adenosine-induced stress was performed in 39 nonstenotic single vein grafts and 20 nonstenotic sequential vein grafts, as well as in 15 stenotic vein grafts before and 7.3 weeks +/- 1.5 after successful PCI. We evaluated the following parameters (in terms of mean values +/- SDs): average peak velocity (APV) at baseline, stress APV, and velocity reserve. Parameters in nonstenotic single and sequential vein grafts were compared by means of unpaired two-tailed Student t testing. To evaluate changes in velocities before and after PCI, a paired two-tailed Student t test was used. P <.05 was considered to indicate a statistically significant difference. RESULTS: Reference values in single vein grafts for baseline APV, stress APV, and velocity reserve were 8.6 cm/sec +/- 3.4, 20.2 cm/sec +/- 9.5, and 2.4 +/- 0.8, respectively. In sequential vein grafts, significantly higher values for baseline APV (12.2 cm/sec +/- 5.0) and stress APV (27.2 cm/sec +/- 10.6) but a similar velocity reserve (2.3 +/- 0.7) were found. Significant improvements were observed after PCI in baseline APV (before PCI: 9.2 cm/sec +/- 6.6; after PCI: 12.9 cm/sec +/- 7.9; P =.008) and stress APV (before PCI: 12.9 cm/sec +/- 6.3; after PCI: 27.1 cm/sec +/- 13.9; P <.001). No improvement in velocity reserve was observed. CONCLUSION: Significantly higher absolute velocity and flow values were observed in sequential versus single vein grafts, underscoring the need for separate functional reference values for different graft types. Graft function showed significant improvement after PCI to the point that it was restored or nearly restored to reference values.

Adenosine↗
PubMed2002

Left ventricular remodeling early after aortic valve replacement: differential effects on diastolic function in aortic valve stenosis and aortic regurgitation.

OBJECTIVES: The aim of this study was to evaluate the effect of aortic valve replacement (AVR) on left ventricular (LV) function and LV remodeling, comparing patients with aortic valve stenosis to patients with aortic regurgitation. BACKGROUND: Aortic valve disease is associated with eccentric or concentric LV hypertrophy and changes in LV function. The relationship between LV geometry and LV function and the effect of LV remodeling after AVR on diastolic filling, in patients with aortic valve stenosis compared with aortic regurgitation, are largely unknown.Nineteen patients with aortic valve disease (12 aortic valve stenosis, 7 aortic regurgitation) were studied using magnetic resonance imaging to assess LV geometry and LV function before and 9 +/- 3 months after AVR. Ten age-matched healthy males served as control subjects. RESULTS: Before AVR, the ratio between left ventricular mass index (LVMI) and left ventricular end-diastolic volume index (LVEDVI) was only increased in patients with aortic valve stenosis (1.37 +/- 0.16 g/ml) compared with control subjects (0.93 +/- 0.08 g/ml, p < 0.05). After AVR, LVMI/LVEDVI decreased significantly in aortic valve stenosis (to 1.15 +/- 0.14 g/ml, p < 0.0001), but increased significantly in aortic regurgitation (1.02 +/- 0.20 g/ml to 1.44 +/- 0.27 g/ml, p < 0.0001). Before AVR, diastolic filling was impaired in both aortic valve stenosis and aortic regurgitation. Early after AVR, diastolic filling improved in patients with aortic valve stenosis, whereas patients with aortic regurgitation showed a deterioration in diastolic filling. CONCLUSIONS: Early after AVR, patients with aortic valve stenosis show a decrease in both LVMI and LVMI/LVEDVI and an improvement in diastolic filling, whereas in patients with aortic regurgitation, LVMI decreases less rapidly than LVEDVI, causing concentric remodeling of the LV, most likely explaining the observed deterioration of diastolic filling in these patients.

Adult↗