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O Kamp

Publications and source records attributed to O Kamp.

At least 37 records · Page 2Linked to original sources
PubMed2001

Intermittent harmonic imaging and videodensitometry significantly enhance ability of intravenous air-filled ultrasonographic contrast agent to produce ventricular and myocardial opacification.

We used visual and videodensitometric evaluation to investigate the influence of intermittent harmonic imaging (IHI) compared with intermittent fundamental imaging on cavity and myocardial signal intensity after administration of the air-filled transpulmonary contrast agent BY963. Twelve patients were studied with intermittent fundamental imaging and IHI after administration of 5 mL and 10 mL of contrast agent. Contrast effect was graded in the parasternal short-axis view. Visually, IHI improved opacification of both the right and left ventricular cavities, especially the left. Densitometrically, right ventricular opacification did not differ significantly between imaging modalities, whereas left ventricular cavity opacification was significantly higher when using IHI. Myocardial opacification was observed in a small minority of segments when assessed by visual estimation, whereas videodensitometry revealed opacification in 42 of 48 anterior, 39 of 48 posterior, and 42 of 48 septal segments. Differences were not significant between doses. We conclude that with IHI and densitometry, air-filled contrast agents like BY963 show significantly improved performance in producing cavity and myocardial contrast effects.

Adolescent↗
PubMed2001

Quantitative assessment of mechanical prosthetic valve area by 3-dimensional transesophageal echocardiography.

OBJECTIVE: The goal of this study was to assess the geometric orifice area of mechanical valve prostheses by transesophageal 3-dimensional echocardiographic planimetry. METHODS AND RESULTS: Currently used Doppler methods for prosthetic assessment (orifice area-Doppler) were compared with 3D planimetry for orifice area (orifice area-3D) and with manufacturer's values (orifice area-manufacturer) for the corresponding prosthesis types and sizes and with historical controls provided by Doppler literature (orifice area-literature). Twenty-four mechanical valve prostheses (in 22 patients) were studied: 13 in mitral position and 11 in aortic position. Orifice area-manufacturer, orifice area-Doppler, orifice area-literature, and orifice area-3D were 3.6 +/- 1.1 cm(2), 2.3 +/- 0.9 cm(2), 2.4 +/- 0.9 cm(2), and 2.6 +/- 0.7 cm(2), respectively. Orifice area-manufacturer values were significantly larger. Correlation coefficients between orifice area-3D and orifice area-manufacturer, and between orifice area-3D and orifice area-Doppler and orifice area-literature were 0.83, 0.90, and 0.73, respectively (all P < .0001). CONCLUSION: Three-dimensional transesophageal echocardiography is feasible and has good correlation with orifice area-Doppler (in aortic position) and good correlation with orifice area-manufacturer (in aortic and mitral positions) methods.

Adult↗
PubMed2001

Effects of 15 months of 17 beta-estradiol and dydrogesterone on systolic cardiac function according to quantitative and Doppler echocardiography in healthy postmenopausal women.

OBJECTIVE: Our goal was to investigate the short-term and intermediate effects of low-dose hormone replacement therapy on echocardiographic parameters of cardiac function in healthy postmenopausal women. STUDY DESIGN: In a prospective, controlled study 30 healthy postmenopausal women (mean age, 52 +/- 3 years) were randomly assigned to 2 groups. Women in the hormone replacement therapy group (n = 15) received 1 mg micronized 17 beta-estradiol daily sequentially combined with 5 or 10 mg dydrogesterone for 14 days of each 28-day cycle during 12 months and thereafter 2 mg 17 beta-estradiol combined with 10 mg dydrogesterone for a period of 3 months. The control group (n = 15) received no treatment. M-mode, quantitative 2-dimensional, and Doppler echocardiographic measurements were performed at baseline and within the 17 beta-estradiol phase at 3, 12, and 15 months. RESULTS: After 12 months significant differences in change between the 2 groups were found for left ventricular end-diastolic and left ventricular end-systolic diameters, left ventricular mass index, and stroke volume index. These differences were caused by changes in the control group rather than in the hormone replacement therapy group, in which no significant within-group changes were found. All other parameters measured showed no effect. CONCLUSION: Within 15 months of 17 beta-estradiol and dydrogesterone treatment no clinically relevant differences were found in the M-mode, quantitative 2-dimensional, and Doppler echocardiographic parameters measured in this study. It is suggested that 15 months of treatment probably is too short a period for detection of direct effects on the heart itself.

Double-Blind Method↗
PubMed2001

[Mitral stenosis evaluated with three-dimensional echocardiography].

The authors evaluated the possibilities of three-dimensional echocardiography in the assessment of the severity of mitral valve stenosis. In 45 patients, the Doppler pressure half-time method was compared with two three-dimensional echocardiographic methods in the measurement of mitral valve orifice: anyplane echocardiography and surface rendering. There was significant relation between them: r = 0.74 and r = 0.70, both p < 0.0001. In addition, mitral valve stenosis was also quantified by two new indices, such as the doming volume of the mitral apparatus and mitral valve volume. Subgroup analysis revealed relation between atrial fibrillation and decreasing doming volume as well as significantly higher mitral valve volume in patients with critical stenosis. Associated valve abnormalities did not influence the mitral orifice measurement neither by Doppler method nor three-dimensional echocardiography. In conclusion, three-dimensional echocardiography allows reliable assessment of mitral stenosis and moreover provides new quantitative indices, which can be clinically important in the assessment of three-dimensional geometry of the mitral apparatus.

Adolescent↗
PubMed2000

Transesophageal echocardiography for early cardioversion of atrial fibrillation.

Exclusion of thrombi in the setting of atrial fibrillation (AF) has important implications for early cardioversion. Cardioversion guided by transesophageal echocardiography (TEE) is a safe and relatively cost-effective technique with a high accuracy for detecting left-atrial thrombi. Nowadays, TEE-guided cardioversion may help to select patients suitable for early cardioversion. However, the long-term effect of early TEE-guided cardioversion on the maintenance of sinus rhythm needs to be determined.

Anticoagulants↗
PubMed2000

Assessment of myocardial reperfusion by intravenous myocardial contrast echocardiography and coronary flow reserve after primary percutaneous transluminal coronary angioplasty [correction of angiography] in patients with acute myocardial infarction.

BACKGROUND: This study investigated whether the extent of perfusion defect determined by intravenous myocardial contrast echocardiography (MCE) in patients with acute myocardial infarction (AMI) treated by primary percutaneous transluminal coronary angioplasty (PTCA) relates to coronary flow reserve (CRF) for assessment of myocardial reperfusion and is predictive for left ventricular recovery. METHODS AND RESULTS: Twenty-five patients with first AMI underwent intravenous MCE with NC100100 with intermittent harmonic imaging before PTCA and after 24 hours. MCE before PTCA defined the risk region and MCE at 24 hours the "no-reflow" region. The no-reflow region divided by the risk region determined the ratio to the risk region. CFR was assessed immediately after PTCA and 24 hours later. Left ventricular wall motion score indexes were calculated before PTCA and after 4 weeks. CFR at 24 hours defined a recovery (CFR >/=1.6; n=17) and a nonrecovery group (CFR <1.6; n=8). Baseline CFR did not differ between groups. MCE ratio to the risk region was smaller in the recovery group compared with the nonrecovery group (34+/-49% vs 81+/-46%, P=0.009). A ratio to the risk region of </=50% defined an MCE reperfusion group. It was associated with improvement of CFR from 1.67+/-0.47 at baseline to 2. 15+/-0.53 at 24 hours (P<0.001) and of regional wall motion score index from 2.6+/-0.5 to 1.9+/-0.5 at 4 weeks (P<0.001). CONCLUSIONS: Intravenous MCE can be used to define perfusion defects after AMI. Assessment of microcirculation by MCE corresponds to evaluation by CFR. Serial intravenous MCE has the potential to identify patients likely to have improved left ventricular function after AMI.

Aged↗
PubMed2000

Myocardial contrast echocardiography: clinical benefit and practical issues.

Real-time bedside evaluation of myocardial perfusion after intravenous application of microbubbles is the ultimate goal for contrast echocardiography. Over the past decade rapid evolution has occurred in the development of contrast agents, ultrasound equipment tailored to their detection, and image interpretation. This article offers a review of the basic concepts of the technique's background, contrast agent design, and imaging technology. The major clinical indications of myocardial contrast echocardiography are evaluation of acute ischemic syndromes, diagnosis of viable myocardium following AMI, and the detection of CAD using stress contrast perfusion imaging. Furthermore, the article addresses the most significant practical problems and suggested solutions to master those problems. As major new achievements are realistic expectations for the first decade of the twenty-first century, we conclude that the coupling of a new generation of contrast agents with innovative echocardiographic instrumentation will ultimately enable the full potential of myocardial contrast echocardiography to be realized which may revolutionize modern echocardiography.

Acute Disease↗
PubMed1999

NC100100, a new echo contrast agent for the assessment of myocardial perfusion--safety and comparison with technetium-99m sestamibi single-photon emission computed tomography in a randomized multicenter study.

BACKGROUND AND HYPOTHESIS: Myocardial contrast echocardiography using second-generation agents has been proposed to study myocardial perfusion. A placebo-controlled, multicenter trial was conducted to evaluate the safety, optimal dose, and imaging mode for NC100100, a novel intravenous second-generation echo contrast agent, and to compare this technique with technetium-99m sestamibi (MIBI) single-photon emission computed tomography (SPECT). METHODS: In a placebo-controlled, multicenter trial, 203 patients with myocardial infarction > 5 days and < 1 year previously underwent rest SPECT and MCE. Fundamental and harmonic imaging modes combined with continuous and electrocardiogram-- (ECG) triggered intermittent imaging were used. Six dose groups (0.030, 0.100, and 0.300 microliter particles/kg body weight for fundamental imaging; and 0.006, 0.030, and 0.150 microliter particles/kg body weight for harmonic imaging) were tested. A saline group was also included. Safety was followed for 72 h after contrast injection. Myocardial perfusion by MCE was compared with myocardial rest perfusion imaging using MIBI as a tracer. RESULTS: NC100100 was well tolerated. No serious adverse events or deaths occurred. No clinically relevant changes in vital signs, laboratory parameters, and ECG recordings were noted. There was no significant difference between adverse events in the NC100100 (25.7%) and in the placebo group (17.9%, p = 0.3). Intermittent harmonic imaging using the intermediate dose was superior to all other modalities, allowing the assessment of perfusion in 76% of all segments. Eighty segments (96%) with normal perfusion by SPECT imaging also showed myocardial perfusion with MCE. However, a substantial percentage of segments (61-80%) with perfusion defects by SPECT imaging also showed opacification by MCE. This resulted in an overall agreement of 66-81% and a high specificity (80-96%), but in low sensitivity (20-39%) of MCE for the detection of perfusion defects. CONCLUSION: NC100100 is safe in patients with myocardial infarction. Intermittent harmonic imaging with a dose of 0.03 microliter particles/kg body weight can be proposed as the best imaging protocol. Myocardial contrast echocardiography with NC 100100 provides perfusion information in approximately 76% of segments and results in myocardial opacification in the vast majority of segments with normal perfusion as assessed by SPECT. Although the discrepancies between MCE and SPECT with regard to the definition of perfusion defects requires further investigation, MCE with NC 100100 is a promising technique for the noninvasive assessment of myocardial perfusion.

Aged↗
PubMed1999

Non-invasive evaluation of left ventricular function by means of impedance cardiography.

BACKGROUND: Simple, accurate, continuous non-invasive cardiac monitoring during the peri- and postoperative periods for patients at risk of cardiac failure would be very useful. Electrical impedance cardiography (EIC) has been proposed as an accurate method for non-invasive measurement of cardiac function. However, in recent years the accuracy of EIC in stroke volume (SV) measurement has been questioned and this prevented global acceptance of the method. Beside SV, EIC is capable of measuring several other left ventricular contractility indices, which are measured directly from the impedance signal. The aim of this study was to compare these variables with the echocardiographically derived left ventricular wall motion score (WMS) as the reference method. METHODS: In a group of eight coronary artery disease patients we performed a pharmacologically (dobutamine) induced stress test. Echocardiographic and impedance cardiographic recordings were performed simultaneously during four levels of dobutamine infusion. WMS was derived from the simultaneously displayed four-stage echocardiographic image. RESULTS: Analysis of variance showed that the majority of indices changed significantly during the test. Direct correlation with the wall motion score gave very satisfactory results over all stages with the RZ time (r = 0.75, P < 0.001) and Heather index (r = -0.78, P < 0.001). Other correlations were substantially lower. CONCLUSION: The Heather index has to be preferred as indicator of the left ventricular performance. Since EIC is capable of giving continuous information of the left ventricular performance, it might be a valuable method for peri- and postoperative monitoring.

Adrenergic beta-Agonists↗
PubMed1999

Sustained benefit at 10-14 years follow-up after thrombolytic therapy in myocardial infarction.

AIMS: To investigate whether the benefit of thrombolytic therapy was sustained beyond the first decade. We report the 10-14 year outcome of 533 patients who were randomized to treatment with intracoronary streptokinase or to conventional therapy during the years 1980-1985. METHODS AND RESULTS: Details of survival and cardiac events were obtained from the civil registry, from medical records or from the patient's physician. At follow-up, 158 patients (59%) of the 269 patients allocated to thrombolytic treatment and only 129 patients (49%) of the 264 conventionally treated patients were alive. The cumulative 1-, 5- and 10-year survival rates were 91%, 81% and 69% in patients treated with streptokinase and 84%, 71% and 59% in the control group, respectively (P=0.02). Reinfarction during 10-years of follow-up was more frequent after thrombolytic therapy, particularly during the first year. Coronary bypass surgery and coronary angioplasty were more frequently performed after thrombolytic therapy. At 10 years approximately 30% of the patients were free from subsequent cardiac events. Independent determinants of mortality were elderly age, indicators of impaired residual left ventricular function, multivessel disease and an inability to perform an exercise test at the time of hospital discharge. CONCLUSION: Improved survival after thrombolytic therapy is maintained beyond the first decade. Age, left ventricular function, multivessel disease and an inability to perform an exercise test were independent predictors for long-term mortality, as they are predictors for early mortality.

Adult↗
PubMed1999

Importance of left atrial appendage flow as a predictor of thromboembolic events in patients with atrial fibrillation.

AIM: The purpose of this study was to investigate the role of transoesophageal echocardiography in predicting subsequent thromboembolic events in patients with atrial fibrillation. METHODS AND PATIENTS: Transoesophageal echocardiography was performed in 88 patients with documented paroxysmal (n=53) or chronic atrial fibrillation (n=35) to assess morphological and functional predictors of thromboembolic events. Prospective selection was from patients with non-valvular atrial fibrillation who had undergone transoesophageal echocardiography because of previous thromboembolism (n=30); prior to electrical cardioversion (n=31); or for other reasons (n=27). All patients were followed up for 1 year. RESULTS: During the period of follow-up new thromboembolic events occurred in 18 of 88 patients (20%/year); 16 of these patients had a stroke and two a peripheral embolism. Univariate analysis revealed that previous thromboembolism (P<0.005; odds ratio 5.3 [CI 1.9, 12. 1]), history of hypertension (P<0.01; odds ratio 4.0 [CI 1.4, 10.4), presence of left atrial spontaneous echo contrast (P<0.025; odds ratio 3.5 [CI 1.2, 10.0]), and presence of left atrial appendage peak velocity </=0.20 m. s-1(P<0.01; odds ratio 4.1 [CI 1.4, 11.6]) were significantly related to subsequent thromboembolic events. Stepwise logistic regression showed that independent predictors of thromboembolic events were: history of thromboembolism (P<0.005), history of hypertension (P<0.05) and low left atrial appendage peak velocity </=0.20 m. s-1(P<0.01). CONCLUSIONS: In patients with atrial fibrillation, the presence of spontaneous echo contrast in the left atrium, and in particular a low left atrial appendage peak flow velocity, can be used to identify a subgroup of atrial fibrillation patients at either increased or decreased risk of subsequent thromboembolism, which might have important implications for anticoagulation therapy.

Aged↗
PubMed1999

Pacing-induced left ventricular dysfunction. Relationship with coronary perfusion.

In a patient admitted with symptomatic complete heart block, a DDD pacemaker was implanted. Prior to implantation, echocardiography showed normal left ventricular function. Shortly after implantation, acute congestive heart failure developed with extensive regional hypo- and akinetic segments in the anteroseptal, anterolateral and apical region. Subsequent perfusion imaging with methoxyisobuticeisonitrite (MIBI) at rest demonstrated hypoperfusion in the same regions while coronary angiography showed normal epicardial coronary vessels. Thus, impaired regional coronary flow can be associated with cardiac stimulation, inducing marked deterioration of left ventricular function.

Aged↗
PubMed1999

Usefulness of echocardiography to predict inappropriate atrial sensing in single-lead VDD pacing.

Reliable atrial sensing is the prerequisite for restoration of atrioventricular synchrony in patients with single-lead VDD pacing systems. To determine echocardiographic variables associated with inappropriate atrial sensing, 21 consecutive patients with symptomatic second- or third-degree AV block and normal sinus node function were studied. Prior to implantation echocardiographic measurements of end-systolic and end-diastolic dimensions and volumes of the right atrium and right ventricle were performed. All patients underwent implantation of a Medtronic Thera VDD(d) pacemaker with a bipolar Medtronic Capsure electrode. A minimal amplitude of the unfiltered atrial electrocardiogram of > or =0.5 mV was required for permanent lead position and the atrial sensitivity was programmed below the lowest recorded value. Appropriate atrial sensing (atrial triggered ventricular paced complexes/total number of ventricular paced complexes) was assessed during 24-hour Holter monitoring and treadmill exercise testing 3 to 6 weeks after implantation. Inappropriate atrial sensing (<95% correct atrial synchronization during Holter registration and/or <97.5% during exercise testing) was present in nine patients. Right atrial volumes and the right ventricular end-diastolic volume was significantly higher, as compared to patients without inappropriate sensing (12 patients). The right atrial and diastolic volumes had the highest correlation with correct atrial sensing r = 0.83, P<0.0001). Using a postdefined cut-off value of > or =80 mL for the end-diastolic right atrial volume, sensitivity and specificity for inappropriate sensing was 100% and 92%, respectively. These findings show that preimplant echocardiography can identify patients with inappropriate sensing during VDD pacing, in whom DDD pacing should be considered.

Aged↗
PubMed1999

Noninvasive measurement of cardiac output: two methods compared in patients with mitral regurgitation.

In search for the origin of the less reliable cardiac output (CO) estimations by means of electrical impedance cardiography (EIC), the authors hypothesized that cardiac valve pathology might be one of the reasons. Twenty-six patients were examined by means of echo Doppler (ED) and EIC. The cardiac valve status was obtained by means of echocardiography and color Doppler flow, while CO was obtained by means of both methods. Seventeen patients had no valve pathology (nVP) while nine patients had mild to moderate mitral regurgitation (MVR). The overall correlation between the calculation of CO by means of the two methods was good (r = 0.85, p < 0.001, mean difference and standard deviation: 0.20+/-0.74 L/min), while there was no significant difference between the paired values. After division into an nVP and an MVR population, the results showed an even closer agreement between the CO values in the nVP population (r = 0.88, p < 0.001, mean difference and standard deviation: 0.15+/-0.68 L/min). Furthermore, significant differences were found in the first derivative of the impedance (dZ/dt) signals of these groups. Although the agreement between ED and EIC was slightly lower in the MVR population, EIC reliably estimated CO, even in case of MVR. The impedance signal itself gave an indication for the existence of MVR.

Adult↗
PubMed1999

Long-term effects of growth hormone (GH) replacement in men with childhood-onset GH deficiency.

Short term GH replacement therapy has been shown to improve body composition and exercise capacity. It is not yet known whether GH replacement remains beneficial over the long term. We assessed the effects of long term GH replacement on body composition, bone mineral density, and cardiac function. Thirty-eight men with childhood-onset GH deficiency were studied for a period of 3-5 yr. Measurements included anthropometry, computed tomographic scanning of abdomen and upper leg, bone densitometry, echo cardiography, and bicycle ergometry. The initial GH dose of 1-3 IU/m2 x day (9-27 microg/kg) was gradually tapered to 1.30+/-0.38 IU/m2 x day (11 g/kg), aiming at physiological insulin-like growth factor I levels. During the study, leg muscle mass progressively increased by 28.7% (P<0.001). Subcutaneous and intraabdominal fat decreased by 30.9% and 46.0%, respectively, after 1 yr (both P<0.001), but demonstrated a partial regain thereafter. Bone mineral density at the lumbar spine, femoral neck, and trochanter gradually increased by 9.6%, 11.1%, and 16.2%, respectively (all P<0.001). Left ventricular mass exceeded baseline values by 14.1% after 1 yr (P<0.001), but returned to pretreatment values thereafter. Stroke volume and cardiac output increased by 16.3% (P = 0.002) and 33.4% (P<0.001), respectively. Maximal work load increased from 189+/-30 to 232+/-41 watts (P<0.001). Thus, long term GH replacement is safe and beneficial. It improves cardiac performance without inducing left ventricular hypertrophy and progressively increases bone mineral density.

Adult↗
PubMed1998

Accuracy and feasibility of contrast echocardiography for detection of perfusion defects in routine practice: comparison with wall motion and technetium-99m sestamibi single-photon emission computed tomography. The Nycomed NC100100 Investigators.

OBJECTIVES: We sought to assess the feasibility and accuracy of myocardial contrast echocardiography (MCE) using standard imaging approaches for the detection of perfusion defects in patients who had a myocardial infarction (MI). BACKGROUND: Myocardial contrast echocardiography may be more versatile than perfusion scintigraphy for identifying the presence and extent of perfusion defects after MI. However, its reliability in routine practice is unclear. METHODS: Fundamental or harmonic MCE was performed with continuous or triggered imaging in 203 patients with a previous MI using bolus doses of a perfluorocarbon-filled contrast agent (NC100100). All patients underwent single-photon emission computed tomography (SPECT) after the injection of technetium-99m (Tc-99m) sestamibi at rest. Quantitative and semiquantitative SPECT, wall motion and digitized echocardiographic data were interpreted independently. The accuracy of MCE was assessed for detection of segments and patients with moderate and severe sestamibi-SPECT defects, as well as for detection of patients with extensive perfusion defects (>12% of left ventricle). RESULTS: In segments with diagnostic MCE, the segmental sensitivity ranged from 14% to 65%, and the specificity varied from 78% to 95%, depending on the dose of contrast agent. Using both segment- and patient-based analysis, the greatest accuracy and proportion of interpretable images were obtained using harmonic imaging in the triggered mode. For the detection of extensive defects, the sensitivity varied from 13% to 48%, with specificity from 63% to 100%. Harmonic imaging remained the most accurate approach. Time since MI and SPECT defect location and intensity were all determinants of the MCE response. The extent of defects on MCE was less than the extent of either abnormal wall motion or SPECT abnormalities. The combination of wall motion and MCE assessment gave the best balance of sensitivity (46% to 55%) and specificity (82% to 83%). CONCLUSIONS: Although MCE is specific, it has limited sensitivity for detection of moderate or severe perfusion defects, and it underestimates the extent of SPECT defects. The best results are obtained by integration with wall motion. More sophisticated methods of acquisition and interpretation are needed to enhance the feasibility of this technique in routine practice.

Contrast Media↗
PubMed1998

Hemodynamic benefits of right ventricular outflow tract pacing: comparison with right ventricular apex pacing.

To assess optimal hemodynamics in relation to stimulation site during right ventricular pacing, 17 consecutive patients who underwent cardiac catheterization were studied. In all patients, right ventricular apex and right ventricular outflow tract stimulation was performed at 85, 100, and 120 beats/min. Cardiac index at both pacing sites was compared using the left ventricular outflow tract continuous wave Doppler technique. Comparison of the two stimulation sites demonstrated that right ventricular outflow tract pacing resulted in a higher cardiac index at 85 beats/min (2.42 +/- 1.2 vs 2.04 +/- 1.0 L/min per m2, P < 0.002) at 100 beats/min (2.78 +/- 1.4 vs 2.35 +/- 1.1 L/min per m2, P < 0.001) and 120 beats/min (3.00 +/- 1.5 vs 2.61 +/- 0.9 L/min per m2, P < 0.001). From a total of 51 paired observations, 45 showed an increase in cardiac index during outflow tract pacing as compared to apex pacing. Right ventricular outflow tract pacing at 120 beats/min resulted in a lower cardiac index than right ventricular apex pacing in patients with significant coronary artery disease and/or impaired left ventricular function (ejection fraction < or = 50%), whereas right ventricular outflow tract pacing produced higher cardiac indices in the absence of these abnormalities. Right ventricular outflow tract pacing resulted in higher cardiac indices as compared to apex pacing in all other subgroups at all other pacing sites tested. It is concluded that stimulation of the right ventricular outflow tract offers a significant hemodynamic benefit during single chamber pacing as compared to conventional apex pacing, particularly in the absence of significant coronary artery disease and/or left ventricular dysfunction.

Adult↗