Search

Loeffler's endocarditis (LE) is the cardiac manifestation of hypereosinophilic syndrome, a rare systemic disease characterized by the sustained production of eosinophils leading to organ damage. Few data, principally by case reports, are available regarding the diagnostic workup in patients with suspected LE. Thus, we have performed a systematic search of the literature dealing with imaging in LE and propose an integrated multimodality imaging approach in the cardiac diagnostics of LE patients. The aim is to provide an updated state-of-the-art review focused on noninvasive and invasive imaging modalities for this rare and underdiagnosed disease. Standard and advanced echocardiography are typically the first cardiac imaging examinations when LE is suspected and they are also used later in follow-up for prognostic stratification and assessing response to treatment. Cardiac magnetic resonance provides a more detailed anatomical and functional evaluation of cardiac chambers, tissue characterization for the presence and extension of myocardial edema and fibrosis, and ventricular thrombi identification. Computed tomography scan and [18F]-fluoro-deoxy-glucose positron emission tomography may be helpful in selected cases to evaluate the cardiac involvement of LE as well as the other noncardiac manifestations of hypereosinophilic syndrome. Endomyocardial biopsy may be considered in patients with high clinical suspicion of LE if noninvasive imaging findings are confusing or not conclusive. The appropriate use of invasive and noninvasive imaging modalities, combining the available techniques with the patients' clinical features, will hopefully lead to early diagnosis, more accurate staging of disease, and timely treatment of LE that may prevent the irreversible myocardial damage of LE and adverse cardiovascular events.

Background Chronic kidney disease is common in patients admitted with acute coronary syndrome and its prevalence dramatically increases with age. Understanding the determinants of adverse outcomes in this extremely high-risk population may be useful for the development of specific treatment strategies and planning of secondary prevention modalities.Aim The aim of this study was to assess the impact of baseline renal function and acute kidney injury on one-year outcome of elderly patients with acute coronary syndrome treated with percutaneous coronary intervention.Methods Patients aged 75 years and older with acute coronary syndrome undergoing successful percutaneous coronary intervention were selected among those enrolled in three Italian multicentre studies. Based on the baseline estimated glomerular filtration rate (eGFR) calculated using the Cockcroft–Gault formula ([(140–age) × body weight × 0.85 if female]/(72 × serum creatinine)* 1.73 m2of body surface area), patients were classified as having none or mild (eGFR ≥60 ml/min/1.73 m2), moderate (eGFR 30–59 ml/min/1.73 m2) or severe (eGFR <30 ml/min/1.73 m2) renal dysfunction. Acute kidney injury was defined according to the Acute Kidney Injury Network classification. All-cause and cardiovascular mortality, non-fatal myocardial infarction, rehospitalisation for cardiovascular causes, stroke and type 2, 3 and 5 Bleeding Academic Research Consortium bleedings were analysed up to 12 months.Results A total of 1904 patients were included. Of these, 57% had moderate and 11% severe renal dysfunction. At 12 months, patients with renal dysfunction had higher rates (P< 0.001) of all-cause (4.5%, 7.5% and 17.8% in patients with none or mild, moderate and severe renal dysfunction, respectively) and cardiovascular mortality (2.8%, 5.2% and 10.2%, respectively). After multivariable adjustment, severe renal dysfunction was associated with a higher risk of all-cause (hazard ratio (HR) 2.86, 95% confidence interval (CI) 1.52–5.37, P= 0.001) and cardiovascular death (HR 3.11, 95% CI 1.41–6.83, P= 0.005), whereas non-fatal events were unaffected. Acute kidney injury incidence was significantly higher in ST-elevation myocardial infarction versus non-ST-elevation acute coronary syndrome patients (11.7% vs. 7.8%, P= 0.036) and in those with reduced baseline renal function (P< 0.001), and it was associated with increased mortality independently from baseline renal function and clinical presentation.Conclusions Baseline renal dysfunction is highly prevalent and is associated with higher mortality in elderly acute coronary syndrome patients undergoing percutaneous coronary intervention. Acute kidney injury occurs more frequently among ST-elevation myocardial infarction patients and those with pre-existing renal dysfunction and is independently associated with one-year mortality.

Supplemental Digital Content is available in the text.

Spontaneous coronary artery rupture is a rare disorder that may develop early into a sudden death due to the abrupt evolution of the associated cardiac tamponade. In some cases the rupture is contained and a false aneurysm develops with slower evolution of clinical signs. The correct diagnosis of spontaneous coronary artery rupture deserves a high level of suspicion; frequently it may be missed because the time window of its evolution seems to be very short or signs of acute coronary syndrome sometimes can prevail, leading to delays in diagnosis or to misdiagnosis. We report the case of a patient presenting a giant pseudoaneurysm of the right coronary artery due to spontaneous coronary artery rupture without any underlying disease. Moreover we present a review of the few cases in the literature, offering a pathophysiological hypothesis linking the site of rupture and clinical presentation.

Transthoracic echocardiography is the first-line imaging modality for evaluating patients with Takotsubo syndrome (TTS). Beyond diagnosis, TTE enables detection of peculiar complications and is useful for risk stratification and management of patients with cardiogenic shock. Cardiac magnetic resonance can be used to detect myocardial edema typically associated with TTS and is helpful in the differential diagnosis with other disease states. Coronary computed tomography angiography can be performed as an alternative to coronary angiography to confirm coronary artery patency. Molecular imaging is a promising approach for identifying patients at increased risk of recurrence.

Aims: To determine the association between baseline creatinine clearance (CrCl), coronary revascularization during index admission, and 1-year mortality in elderly patients with an acute coronary syndrome (ACS).Methods and results: We estimated CrCl using the Cockcroft-Gault (CG) formula in 313 patients aged ≥75 years enrolled in a prospective study of treatment strategies in non ST-elevation ACS (NSTEACS). Patients were stratified into four groups according to CrCl on admission (using a cutoff of 45 ml/min) and coronary revascularization versus medical management. The mean age of the study population was 81 years and the median serum creatinine level on admission was 1.0 mg/dl (interquartile range (IQR) 0.8-1.3). Patients with impaired renal function treated medically had higher in-hospital and 1-year mortality, especially if compared with patients with preserved renal function undergoing revascularization (1-year mortality 22.9% versus 4.9%). Across the spectrum of CrCl categories, coronary revascularization was independently associated with a lower risk of mortality (HR 0.405; 95% CI 0.174-0.940; p=0.035).Conclusions: In elderly patients with NSTEACS, coronary revascularization decreases the risk of 1-year death across each CrCl category, and is one of the most powerful predictors of 1-year outcome.

Purpose To evaluate the usefulness of a new transfemoral device to avoid major complications related to residual type A aortic dissection following ascending aortic replacement.Case Reports Three men (aged 60, 61, and 72 years, respectively) with a residual type A aortic dissection following replacement of the ascending aorta 1, 4, and 5 years prior, respectively, were treated with the Djumbodis Dissection System. The residual dissection developed at the distal anastomosis of the aortic graft and involved all the aortic arch. The Djumbodis Dissection System is an uncovered steel stent, available in 3 lengths (40, 90, 140 mm), pre-mounted on a low pressure (0.3 bars) balloon catheter. The mesh of the device is sufficiently large to bring together the dissected layers without occluding main vital branches. The device was implanted through the femoral artery over a stiff guidewire to exclude the residual false lumen. Satisfactory aortic remodeling was documented in all cases at 1 year.Conclusion The Djumbodis Dissection System might be a purely endovascular treatment to replace open surgery for residual type A aortic dissection. More cases and longer follow-up are required.

We evaluated the impact of major complications on clinical outcome in a series of patients undergoing endovascular repair (EVAR) of descending thoracic aorta. From March 2001 to June 2005, 51 patients underwent EVAR for descending aortic diseases. Thirty-five were treated in emergency (60.7%) and 41 (80.4%) were in III-IV ASA class. There were no deaths, surgical conversion or paraplegia. A neurologic complication occurred in one patient (1.9%). Eleven major systemic complications occurred in 5 patients. One patient showed a primary type I endoleak at discharge, resolved spontaneously after 9 months. Three (5.9%) vascular injuries occurred during the endovascular procedure, requiring an emergency rescue iliac-femoral artery bypass. At follow-up (29+/-14 months), there was an overall mortality rate of 5.1% (3/51); 2 deaths (3.9%) were procedure related. Two secondary EVARs (3.9%) were successfully performed, one for a late type I endoleak six months after EVAR in a traumatic patient, and a second for a late rupture distally to the stent-graft implanted 36 months before in an acute type-B dissected patient. EVAR for descending aortic diseases is associated with decreased mortality and complications, however, long-term follow-up and additional studies are mandatory to detect late failure and to confirm clinical safety of this procedure.

Background: This study compared coronary flow reserve (CFR) estimated by technetium 99m sestamibi imaging with the results obtained with intracoronary Doppler in patients with coronary artery disease. Intraobserver and interobserver reproducibility of the radionuclide-estimated CFR was also assessed. Methods and Results: Fourteen consecutive patients (mean age, 54 ± 7 years) with documented coronary artery disease in whom percutaneous coronary intervention was planned underwent dipyridamole (0.74 mg/kg) sestamibi imaging and intracoronary Doppler within 5 days. Myocardial blood flow (MBF) was estimated by measurement of first transit counts in the pulmonary artery and myocardial counts from single photon emission computed tomography images. Estimated CFR was expressed as the ratio of stress MBF to rest MBF. In the study vessels, CFR was 1.36 ± 0.43 as estimated by sestamibi and 1.39 ± 0.42 by intracoronary Doppler (P= .69). A significant relationship between CFR estimated by sestamibi and CFR obtained by intracoronary Doppler was observed (r = 0.85, P&lt; .001). On Bland-Altman analysis, the mean difference between CFR by sestamibi and by Doppler was 0.03 and the intraclass correlation coefficients for intraobserver and interobserver reproducibility were high (all P&lt; .001) for both global and regional CFR. Conclusions: This study demonstrates a good agreement between CFR estimated by sestamibi imaging and by intracoronary Doppler results and a lack of intraobserver and interobserver variability of this noninvasive approach.

BackgroundThe aim of this study was to compare collateral angiographic circulation (CC), thallium 201 single photon emission computed tomography (SPECT), low-dose dobutamine echocardiography (LDDE), and their combination in identifying viable myocardium beyond a chronic occlusion.

Background.The aim of this study was to compare collateral angiographic circulation (CC), thallium 201 single photon emission computed tomography (SPECT), low-dose dobutamine echocardiography (LDDE), and their combination in identifying viable myocardium beyond a chronic occlusion. Methods and Results.We studied 33 consecutive patients with a chronic occluded coronary artery and regional ventricular dysfunction who underwent dobutamine infusion (5–10 μg · kg–1· min–1), Tl-201 SPECT, and coronary revascularization (15 patients underwent coronary artery bypass grafting and 18 patients percutaneous transluminal coronary angioplasty). Echocardiography and Tl-201 SPECT at rest were repeated 90 ± 48 days after revascularization. For viability assessment, Tl-201 SPECT showed the best sensitivity and accuracy (77% and 72%, respectively) compared with LDDE (64% and 63%, respectively) and CC (74% and 55%, P< .05 vs Tl-201 SPECT). Specificity was significantly better for both Tl-201 SPECT (65%) and LDDE (62%) compared with collateral circulation (27%, P< .001 vs Tl-201 SPECT and LDDE). Furthermore, combined Tl-201 SPECT and LDDE data improved specificity (from 88% to 92%) and positive predictive power (from 75% to 78%) but not global accuracy. A direct relationship between the number of viable segments and global functional recovery after revascularization was found only in the case of Tl-201 SPECT (r= 0.48, P= .04). Conclusions.This study demonstrates that CC has a very low specificity in the evaluation of viability in collateral-dependent myocardium and that LDDE has a very low sensitivity, whereas Tl-201 SPECT is the most reliable method, particularly in akinetic segments, and optimally identifies patients who will mostly benefit from revascularization in terms of ventricular functional improvement. No additional advantages in terms of accuracy were found when Tl-201 SPECT and LDDE data were combined.

Eighty‐three consecutive patients with 85 coronary total occlusions undergoing coronary angioplasty were retrospectively studied. Patients were divided into two groups according to the occlusion age that was<30 days (subacute total occlusion [STO]: 25 patients; range 1–30 days) or>30 days (chronic total occlusion [CTO]: 58 patients; range 3–144 months). All procedures were carried out using a hydrophilic guidewire. Clinical success, consisting of crossing the lesion, balloon dilatation, stent deployment without complication, was 96% in STO and 81% in CTO. Multiple stepwise logistic regression analysis identified a family history of coronary artery disease (CAD), left anterior descending and right coronary artery occlusions as independent predictors of a successful procedure. No major events occurred during or immediately after the angioplasty. After a mean follow‐up of 24 ± 2 months, no difference was found in survival or freedom from myocardial infarction or target vessel revascularization among the STO and CTO patients. Successful recanalization by using a hydrophilic guidewire was achieved in a high percentage of chronic total occlusions with a low incidence of complications and a satisfactory late clinical outcome. Family history of CAD and occlusion of left anterior descending or right coronary arteries are independent predictors of procedural success.

Background: The aim of this study was to evaluate the accuracy of low-dose dobutamine echocardiography (DE) and resting thallium 201 single photon emission computed tomography (SPECT) alone and in combination for prediction of functional recovery at late follow-up (1 year) after revascularization. Methods and Results: Twenty-six patients with coronary artery disease and ventricular dysfunction (ejection fraction, 42% ± 9%) underwent DE and Tl-201 SPECT 14 ± 9 (mean ± SD) days before revascularization and repeated echocardiography 12 ± 5 months thereafter. Discriminant analysis was applied to combine Tl-201 SPECT and DE data to classify dysfunctional segments as viable or nonviable. In 78 akinetic/dyskinetic revascularized segments, Tl-201 SPECT provided a sensitivity of 83% and a specificity of 55%, whereas DE showed a sensitivity of 60% and a specificity of 91%, for prediction of improvement in regional function at follow-up. The combination of data through use of discriminant analysis provided a sensitivity of 80% and a specificity of 86%, with an overall accuracy of 82%, significantly higher than DE (71%; P &lt; .05) and Tl-201 SPECT (73%; P &lt; .05) alone. Moreover, discriminant analysis identified 12 (75%) of 16 patients with and 8 (80%) of 10 patients without significant improvement in ejection fraction at follow-up, with an accuracy of 77%. Conclusions: The combination of Tl-201 SPECT and DE data provides higher accuracy than either technique alone for prediction of recovery of regional and global function after revascularization.

Background.The aim of this study was to evaluate the accuracy of low-dose dobutamine echocardiography (DE) and resting thallium 201 single photon emission computed tomography (SPECT) alone and in combination for prediction of functional recovery at late follow-up (1 year) after revascularization. Methods and Results.Twenty-six patients with coronary artery disease and ventricular dysfunction (ejection fraction, 42% ± 9%) underwent DE and Tl-201 SPECT 14 ± 9 (mean ± SD) days before revascularization and repeated echocardiography 12 ± 5 months thereafter. Discriminant analysis was applied to combine Tl-201 SPECT and DE data to classify dysfunctional segments as viable or nonviable. In 78 akinetic/dyskinetic revascularized segments, Tl-201 SPECT provided a sensitivity of 83% and a specificity of 55%, whereas DE showed a sensitivity of 60% and a specificity of 91%, for prediction of improvement in regional function at follow-up. The combination of data through use of discriminant analysis provided a sensitivity of 80% and a specificity of 86%, with an overall accuracy of 82%, significantly higher than DE (71%; P< .05) and Tl-201 SPECT (73%; P< .05) alone. Moreover, discriminant analysis identified 12 (75%) of 16 patients with and 8 (80%) of 10 patients without significant improvement in ejection fraction at follow-up, with an accuracy of 77%. Conclusions.The combination of Tl-201 SPECT and DE data provides higher accuracy than either technique alone for prediction of recovery of regional and global function after revascularization. (J Nucl Cardiol 2002;9:174-82.)

It is known that contractile reserve may be blunted if perfusion and coronary flow reserve are reduced. Thus, it is conceivable that the predictive accuracy of dobutamine echocardiography may differ according to perfusion tracer uptake. The aim of this study was therefore to assess the relationship between the level of thallium-201 uptake and the accuracy of dobutamine echocardiography in identifying reversible dysfunction. Sixty-nine patients (age 59±8 years, ejection fraction 40%±11%) with chronic coronary artery disease scheduled for coronary revascularisation were studied. All patients underwent rest 201Tl single-photon emission tomography and two-dimensional echocardiography at rest and during low-dose dobutamine infusion on the same day before revascularisation and repeated echocardiography at least 30 days thereafter. At follow-up, recovery of function was observed in 49% of 339 dysfunctional segments. The percentage of segments with post-revascularisation recovery of function and the percentage with contractile reserve increased in parallel with 201Tl uptake both in the total group of segments (?2=35.5, P<0.0001 and ?2=35.9, P<0.0001, respectively) and among the 183 akinetic segments (?2=44.4, P<0.0001 and ?2=14.6, P<0.05, respectively). The dysfunctional segments were divided into three groups according to 201Tl uptake: (a) uptake <65%, (b) uptake between 65% and 79%, (c) uptake >80%. The positive predictive value increased significantly with the level of 201Tl uptake, and was suboptimal (46%) in akinetic segments with severely reduced 201Tl uptake. The negative predictive value decreased significantly with 201Tl uptake, and it was less than suboptimal (29%) in akinetic segments with normal tracer uptake. Sensitivity was lower in the subset of akinetic segments (42%–63%) than in all dyssynergic segments (63%–76%), whereas specificity was very high in akinetic segments (80%–84%). It is concluded that the accuracy of low-dose dobutamine echocardiography in predicting reversibility of regional dysfunction varies considerably according to 201Tl uptake at rest and to the severity of regional dysfunction.

Accurate assessment of myocardial viability permits selection of patients who would benefit from myocardial revascularization. Currently, rest-redistribution thallium-201 scintigraphy and low-dose dobutamine echocardiography are among the most used techniques for the identification of viable myocardium. Thirty-one consecutive patients (all men, mean age 60±8 years) with chronic coronary artery disease and reduced left ventricular ejection fraction (31%±7%) were studied. Rest 201Tl single-photon emission tomography (SPET), low-dose dobutamine echocardiography and radionuclide angiography were performed before revascularization. Radionuclide angiography and echocardiography were repeated after revascularization. An a/dyskinetic segment was considered viable on 201Tl SPET when tracer uptake was >65%, while improvement on low-dose dobutamine echocardiography was considered a marker of viability. Increase in global ejection fraction was considered significant at ≥5%. In identifying viable segments, rest 201Tl SPET showed higher sensitivity than low-dose dobutamine echocardiography (72% vs 53%,P<0.05), while specificity was not significantly different (86% vs 88%). In 17 patients, global ejection fraction increased ≥5% (group 1) while in 14 it did not (group 2). A higher number of a/dyskinetic segments were viable on 201Tl SPET in group 1 than in group 2 (2.6±1.9 vs 0.6±1.2,P<0.005), while no significant differences were observed on low-dose dobutamine echocardiography (1.7±1.6 vs 1.1±1.6). A significant correlation was found between the number of a/dyskinetic segments viable on 201Tl SPET and post-revascularization changes in ejection fraction (r=0.52,P<0.05), but such a correlation was not observed for low-dose dobutamine echocardiography. Using as the cut-off the presence of at least one viable a/dyskinetic segment, rest 201Tl SPET had a higher sensitivity (82% vs 53%,P=0.07) and showed a trend towards higher accuracy and specificity (77% vs 58%, and 71% vs 64%, respectively) as compared with low-dose dobutamine echocardiography. In conclusion, these findings suggest that when severely reduced global function is present, rest 201Tl SPET evaluation of viability is more accurate than low-dose dobutamine echocardiography for the identification of patients who will benefit most from revascularization.

In 14 patients with severe congestive heart failure, left ventricular pressure (measured by tip manometer) and derived variables were measured before and every 10 minutes after administration of oral milrinone (10 mg) for 50 minutes along with measurements of coronary sinus blood flow and drug plasma levels. Arterial and coronary sinus catecholamines were measured only before and 50 minutes after milrinone. Left ventricular pressure, volume (as determined by angiography) and derived indexes were simultaneously assessed at matched atrial paced heart rate before and 60 minutes after milrinone. Three patients who did not achieve a therapeutic plasma level (<150 ng/ml) were excluded.

Abstract.: The purpose of this study was to evaluate whether combined evaluation by discriminant analysis of rest-redistribution thallium-201 tomography and low-dose dobutamine echocardiography enhances the accuracy in identifying viable myocardium in patients with chronic coronary artery disease. Rest-redistribution 201Tl has high sensitivity but low specificity in identifying viable myocardium, while the opposite is true for low-dose dobutamine echocardiography. Forty-six patients underwent low-dose dobutamine echocardiography and rest-redistribution 201Tl tomography on the same day. Rest echocardiography was repeated at least 30 days (mean 40±20) after myocardial revascularization. Discriminant analysis was applied to the results of 201Tl tomography and dobutamine echocardiography to classify a/dyskinetic segments as viable or non-viable. In 92 a/dyskinetic segments that were revascularized, rest-redistribution 201Tl tomography yielded an accuracy of 75%, while the accuracy of dobutamine echocardiography was 70% (P<0.05). When discriminant analysis was used, the combined evaluation gave an accuracy of 83% (P<0.05 vs both tests). These findings demonstrate that low-dose dobutamine echocardiography and 201Tl imaging are useful and complementary techniques for identifying viable myocardium in patients with chronic coronary artery disease. Combined evaluation by discriminant analysis significantly improves accuracy, although the cost-effectiveness of such an approach remains to be determined.

Objectives. This study was designed to increase asynchrony with sequential atrioventricular (AV) pacing and to study its effects on left ventricular isovolumetric relaxation, rapid filling and stiffness.

Objectives: There is growing evidence that myocardial segments with reverse redistribution are viable in patients with chronic coronary artery disease. The aim of this study was to assess the effects of myocardial revascularization on systolic function and thallium-201 uptake in such segments. Methods: Rest-redistribution thallium-201 tomography before and after myocardial revascularization was performed in 47 patients with chronic coronary artery disease. Regional function was evaluated by two-dimensional echocardiography before and after revascularization according to a 3-point scale (1=normal, 2=hypokinetic, 3=a/dyskinetic). Improvement of dysfunctional segments was defined when systolic function score decreased ≥1 after revascularization. Reverse redistribution was defined as ≥8% decrease in relative thallium-201 uptake between rest and redistribution images. Results: Reverse redistribution was found in 27 (57%) of 47 patients, corresponding to 60 (11%) of 564 myocardial segments. Of such segments, 24 (40%) had normal systolic function, 19 (32%) were hypokinetic, and 17 (28%) were a/dyskinetic. Thirty-six segments underwent myocardial revascularization, and reverse redistribution was no longer present in 86% of them subsequent to the procedure. Of 26 dyssynergic segments with reverse redistribution subjected to revascularization, 18 (69%) improved at follow-up. Conclusions: The findings of the present study indicate that reverse redistribution is a reversible phenomenon and is often associated with improvement of systolic function following revascularization in patients with chronic coronary artery disease.

Objectives. This study evaluated the relation between reversible segmental left ventricular dysfunction and frequency domain measures of heart period variability in patients with coronary artery disease.

Thirty-six patients with significant coronary artery stenosis and no previous myocardial infarction and 25 subjects with normal coronary arteries underwent 99mTc RNV before and after coronary vasodilatation induced by dipyridamole, 0.75 mg/kg, given IV over 10 min. In subjects with normal coronary arteries, dipyridamole induced an increase in LVEF (from 66±8 to 76±8 percent; mean±SD; p<0.001); in patients with significant coronary artery stenosis (≥75 percent narrowing of at least one major vessel), dipyridamole injection did not affect LVEF (from 63±12 to 62±12 percent). In ten patients a complete, successful PTCA was performed and the RNV with the dipyridamole test repeated. The EF did not change with the dipyridamole test before PTCA (63±7 to 65±9 percent), but increased significantly after PTCA (62±11 to 70±9 percent; p<0.01). Sensitivity and specificity of EF changes after dipyridamole infusion were 75 and 76 percent, respectively. The test produced no major side effects or complications. Radionuclide angiography with dipyridamole helps to detect coronary artery stenosis and might be used to assess the effects of angioplasty on coronary flow reserve.

AbstractThe impact of the duration of atrioventricular (AV) delay on obstruction in hypertrophic cardiomyopathy was evaluated in 12 patients by cardiac catheterization, and in 8 of them also by Doppler echocardiography. The AV delay was programmed in random order at 125, 100 and 75 ms in the invasive study and at 120, 100 and 80 ms after pacemaker implantation. The arterial pressure did not changed throughout the studies, whereas the gradient decreased significantly by reducing the AV delay value; the greater gradient reduction was obtained, in both studies, with the AV delay set between 75 or 80 and 100 ms. QRS duration increased significantly by reducing the AV delay during both studies. The widest QRS was not associated with the smallest gradient in all patients. Changes in gradients were similar during the invasive and noninvasive protocols.