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Marta Sitges

Publications and source records attributed to Marta Sitges.

At least 19 recordsLinked to original sources

Left ventricular electromechanical delay in patients with heart failure and normal QRS duration and in patients with right and left bundle branch block.

AIMS: We sought to define the reference values of intra-left ventricular (LV) electromechanical delay (EMD), and to assess the prevalence (and pattern) of intra-LV dyssynchrony in patients with heart failure (HF) and normal QRS and in patients with right and left bundle branch block. METHODS AND RESULTS: We used tissue Doppler imaging echocardiography and a six-LV wall model to study LV EMD in 103 patients [41 with HF and normal QRS, 22 with right bundle branch block (RBBB), and 40 with left bundle branch block (LBBB)], and in 59 controls. In controls, the median intra-LV EMD was 17 ms, (inter-quartile range 13-30); 95% of controls had a value < or =41 ms. Patients showed a longer intra-LV EMD than controls: 33 ms (20-57) in patients with normal QRS, 32 ms (23-50) in RBBB patients, and 50 ms (30-94) in LBBB patients. Intra-LV dyssynchrony (defined as intra-LV EMD >41 ms) was present in 39, 36, and 60% of the patients, respectively. On average, HF patients showed the same pattern of activation as controls, from the septum to the posterior wall, but activation times were significantly prolonged. In RBBB patients the activation sequence was directed from inferior to anterior and in LBBB from anterior to inferior wall. CONCLUSIONS: Left ventricular dyssynchrony was present in several patients with HF and normal QRS, and in patients with RBBB; conversely, 40% of LBBB patients showed values of LV EMD within the normal range. Left ventricular activation sequence was different between groups. Assessment of LV synchronicity by means of imaging techniques may be more important than QRS duration or morphology in selecting patients for cardiac resynchronization treatment.

Aged↗

Effects of right ventricular pacing on intra-left ventricular electromechanical activation in patients with native narrow QRS.

Some patients with right ventricular (RV) apical pacing show contractile asynchrony of the left ventricle. Whether the asynchrony is due to RV pacing or was a preexistimg condition remains unknown. The aim of this study was to evaluate how much pacing from the RV apex affects left ventricular (LV) electromechanical activation and to assess whether the extent of LV asynchrony during RV pacing can be predicted by clinical, electrocardiographic, or echocardiographic findings obtained during spontaneous rhythm. We evaluated 56 patients with narrow QRS and preserved atrioventricular conduction who received permanent backup RV pacing. Intra-LV electromechanical activation was assessed during spontaneous rhythm and during pacing using tissue Doppler echocardiography. An abnormal intra-LV electromechanical delay (EMD) (defined as a >41-ms difference between the faster and slower activated LV wall) was found in 15 patients (27%) during spontaneous rhythm and 28 patients (50%) during RV pacing (p<0.001). Of the 9 baseline variables (age, gender, history of heart failure, QRS duration in spontaneous rhythm and during pacing, LV end-diastolic and end-systolic diameters, LV ejection fraction, and intra-LV EMD in spontaneous rhythm), an abnormal baseline intra-LV EMD and QRS duration of >85 ms were independent predictors of an abnormal intra-LV delay during RV pacing. RV apical pacing induces asynchrony of LV contractions in a substantial percentage of patients but not in all. Although normal baseline intra-LV electromechanical activation cannot exclude the development of significant asynchrony during RV pacing, the presence of preimplant LV asynchrony predicts for a worsening of this detrimental effect.

Aged↗

Relation of response to cardiac resynchronization therapy to left ventricular reverse remodeling.

Cardiac resynchronization therapy (CRT) reverses left ventricular (LV) remodeling in patients with congestive heart failure. However, the mechanisms leading to the clinical response to CRT remain unclear. The aim of this study was to analyze whether patients who improve clinically have greater LV reverse remodeling than nonresponders after a 12-month follow-up period. The sample comprised 64 consecutive patients with heart failure, complete left bundle branch block, and LV ejection fractions (EFs) < or =35% who were treated with CRT. Doppler echocardiographic scans were taken just before and immediately after the implantation of the pacemakers and at 6- and 12-month follow-up examinations. LV diameters, volumes, and EFs were compared. Responders were defined as those patients who were alive without cardiac transplantation and with > or =10% improvement in the 6-minute walking test after 1 year of follow-up. There were no clinical differences at baseline between responders and nonresponders. At 6- and 12-month follow-up, LV dimensions decreased significantly in responders but did not change in nonresponders. Furthermore, LVEFs improved only in responders. In conclusion, patients who clinically respond to CRT have greater LV reverse remodeling than nonresponders after 6 and 12 months of follow-up. The effect of CRT on LV remodeling may explain, at least in part, the clinical benefit of this therapy.

Aged↗

Anodal capture in cardiac resynchronization therapy implications for device programming.

INTRODUCTION: Right ventricular (RV) anodal capture (AC) has been reported in cardiac resynchronization therapy (CRT), when left ventricular (LV) pacing uses pseudobipolar (LV tip to RV proximal electrode) configuration. The aim of the study was to analyze the prevalence of AC and its implications for device programming. METHODS AND RESULTS: When AC occurred, the resulting QRS morphology was evaluated with the following pacing modes: (1) LV tip pacing plus RV AC, (2) Biventricular (BiV) pacing (i.e., both LV and RV tip pacing), and (3) BiV pacing plus RV AC. Several interventricular pacing (VV) intervals from 50 ms of LV preactivation to 30 ms of RV preactivation were tested in modes 2 and 3. From 38 consecutive patients, AC was achieved in 14 (in 74% of the pacemakers and in none of the defibrillators). LV tip pacing plus RV AC obtained narrower QRS than BiV pacing at all VV intervals in seven of the patients with AC (50%). When BiV pacing is combined with RV AC, it produced a ventricular depolarization through two wave fronts (one from the LV tip and the second from either the ring or the tip of the RV lead depending on the VV interval programmed). CONCLUSIONS: AC obtained the narrowest QRS of all tested pacing modes in a significant proportion of patients undergoing CRT. Though the stimulus was delivered from three sites (BiV pacing plus RV AC mode), only two wave fronts of ventricular activation were seen by ECG.

Aged↗

[Clinical and echocardiographic follow-up of patients with hypertrophic obstructive cardiomyopathy treated by percutaneous septal ablation].

INTRODUCTION AND OBJECTIVES: Alcohol septal ablation is a therapeutic option for patients with hypertrophic obstructive cardiomyopathy who remain symptomatic despite medical treatment. Our aim was to monitor clinical and echocardiographic progression in patients with hypertrophic obstructive cardiomyopathy treated by septal ablation at our center. METHODS: Thirty-five septal ablations were performed in 34 patients (79% male) who had symptomatic hypertrophic obstructive cardiomyopathy despite optimum medical treatment. The procedure was successful in 32 (i.e., the reduction in left ventricular outflow tract pressure gradient, or LVOTPG, was >50%). During clinical and echocardiographic follow-up, New York Heart Association (NYHA) functional class and LVOTPG were monitored. RESULTS: The patients' mean age was 63 (12) years. The mean follow-up period was 9 (3) months. Immediately after septal ablation, LVOTPG decreased significantly, from 74.2 (25.3) mm Hg to 26 (25) mm Hg (P<.001), and remained low throughout follow-up. Moreover, echocardiography showed that the interventricular septum thickness also decreased during follow-up, from 19 (3) mm to 15 (2) mm (P<.0001). A significant improvement in NYHA functional class (from 93% in class III-IV to 84% in class I-II) was also observed. Two deaths occurred within 48 hours after the procedure. The most frequent complication was complete heart block (20%; n=6). CONCLUSIONS: Alcohol septal ablation is effective in patients with hypertrophic obstructive cardiomyopathy who remain symptomatic despite medical treatment. However, the procedure is associated with a significant rate of complications and should, therefore, be reserved for selected patients, in particular for elderly patients and those with comorbid conditions.

Adult↗

Short-term transdermal estradiol enhances nitric oxide synthase III and estrogen receptor mRNA expression in arteries of women with coronary artery disease.

OBJECTIVE: To analyze the short-term effects of estradiol (E2) on the expression of nitric oxide synthase (NOS III) and estrogen receptors (ER) alpha and beta. METHODS: We studied 20 post-menopausal women with coronary artery disease (CAD) undergoing CABG surgery with left internal mammary artery (LIMA) grafting. Ten women received treatment with transdermal E2 prior to surgery (48-72 h) and 10 did not. The distal segment of the LIMA was excised and processed to determine mRNA expression of NOS III and ER alpha and beta (RT-PCR). Expression of NOS III and ER alpha and beta was measured in arbitrary densitometric units (ADUs) relative to GPdH expression, constitutively expressed in human vessels. RESULTS: NOS III and ER alpha and beta mRNA expression was enhanced in women treated with E2 as compared to the control group (NOS III: 1.69+/-0.61 versus 1.14+/-0.48 ADUs, p=0.04; ER alpha: 6.52+/-6.80 versus 1.83+/-1.22 ADUs, p=0.04; ER beta: 4.20+/-3.42 versus 1.56+/-0.59 ADUs, p=0.03). ER alpha, but not ER beta expression, correlated with NOS III expression (r=0.70, p<0.001). CONCLUSIONS: After treatment with E2, NOS III, ER alpha, and ER beta mRNA expression was enhanced in arterial vessels of postmenopausal women with CAD. NOS III mRNA expression was only correlated to ER alpha expression, suggesting that NOS III activation could be more mediated by ER alpha.

Administration, Cutaneous↗

Predictors of lack of response to resynchronization therapy.

About 30% of patients treated with cardiac resynchronization therapy (CRT) do not respond to treatment. The aim of this study was to identify clinical predictors of lack of improvement in patients receiving CRT. From 197 consecutive patients scheduled to receive CRT, 143 fulfilled the inclusion criteria. Mean age was 68 +/- 7 years and 79% were men. Heart failure was due to ischemic heart disease in 49 patients (34%). Mean QRS duration was 165 +/- 26 ms, and left ventricular ejection fraction was 27 +/- 7%. Nonresponder patients were defined as those who died of heart failure, underwent heart transplantation, or did not increase the distance walked in 6 minutes >10%. At 6-month follow-up, there were 28 nonresponders (20%). Among nonresponders, 2 patients received a heart transplantation and 9 patients died of heart failure. In logistic regression analysis, independent predictors of lack of response to CRT were ischemic heart disease (odds ratio [OR] 2.9, 95% confidence interval [CI] 1.2 to 7; p = 0.023), severe mitral regurgitation (OR 3.5, 95% CI 1.3 to 9; p = 0.014), and left ventricular end-diastolic diameter > or =75 mm (OR 3.1, 95% CI 1.1 to 8; p = 0.026). Patients with these 3 predictors had a probability response of 27%.

Aged↗

Evaluation of left ventricular outflow tract area after septal reduction in obstructive hypertrophic cardiomyopathy: a real-time 3-dimensional echocardiographic study.

BACKGROUND: The comparative impact of percutaneous alcohol septal reduction (ASR) and surgical myectomy on the left ventricular outflow tract (LVOT) area in patients with obstructive hypertrophic cardiomyopathy (HC) is not well defined. Real-time 3-dimensional echocardiography (RT3DE) provides accurate information about the LVOT geometry and shape. We aimed to analyze the change in LVOT area after septal reduction interventions in patients with obstructive HC using RT3DE. METHODS: Thirty-one HC patients (mean age 53 +/- 17 years) undergoing ASR (n = 14) or myectomy (n = 17) were studied at baseline and during follow-up with RT3DE. LVOT area was measured after observing the LVOT in the 3D space as the smallest area during midsystole. LVOT pressure gradients were determined by conventional continuous wave Doppler. RESULTS: Overall, LVOT area increased from 0.86 +/- 0.20 to 2.50 +/- 0.88 cm2 (P < .01), and the resting LVOT pressure gradient decreased from 64 +/- 41 to 16 +/- 10 mm Hg (P < .01) after a median follow-up of 3 months after intervention (range 1-24 months). A similar significant decrease in LVOT pressure gradients was seen in myectomy and ASR groups (from 62 +/- 39 to 12 +/- 5 mm Hg and from 67 +/- 43 to 21 +/- 14 mm Hg, respectively, P < .01 in between each group, and P = NS between both groups). However, the increase in LVOT area was greater in myectomy than in ASR group (from 0.81 +/- 0.22 to 2.90 +/- 0.64 cm2 and 0.93 +/- to 0.16 to 2.02 +/- 0.92 cm2, respectively, P < .01 between both groups). CONCLUSION: RT3DE demonstrated an effective increase in LVOT area after both ASR and myectomy. This technique may be useful for assessing the results of septal reduction in patients with obstructive HC.

Adolescent↗

Quantitative analysis of left atrial function during left ventricular ischemia with and without left atrial ischemia: a real-time 3-dimensional echocardiographic study.

Left atrial (LA) systolic and diastolic function were analyzed in an animal model of acute left ventricular ischemia with LA ischemia by proximal left circumflex coronary artery occlusion or without LA ischemia by midleft anterior descending coronary artery occlusion (7 sheep in each group). LA pressures and LA volumes were simultaneously recorded using a catheter and real-time 3-dimensional echocardiography, respectively. LA stroke volume represented 63% of left ventricular stroke volume during left anterior descending coronary artery occlusion, but only 32% during left circumflex coronary artery occlusion. This animal study with 3-dimensional echocardiographic determination of absolute LA volumes demonstrated dramatic depression of LA function during proximal left circumflex coronary artery occlusion as compared with left anterior descending coronary artery occlusion.

Animals↗

[Impaired endothelium-dependent forearm vasodilation in idiopathic dilated cardiomyopathy is related to severe left ventricular dysfunction and elevated serum tumor necrosis factor levels].

INTRODUCTION AND OBJECTIVES: Endothelial dysfunction has been found in patients with idiopathic dilated cardiomyopathy (IDC), but its mechanism remains unknown. Our aim was to investigate whether forearm endothelium-dependent vasoreactivity correlates with cardiac disease severity or neurohormonal activation. PATIENTS AND METHOD: We studied 23 patients with IDC and 10 healthy sex- and age-matched controls using brachial artery ultrasound to assess flow-mediated dilation (FMD) and nitroglycerin-induced vasodilation (NIV). In the IDC group, we determined plasma neurohormone and cytokine levels at the same time. RESULTS: FMD was significantly less in the IDC group compared with the control group [--0.06 (2.8)% vs 4.4 (4.6)%, respectively; P<.01], whereas NIV was similar in both groups [15.0 (6.4)% vs 14.0 (7.4)%, respectively; P=NS]. FMD was significantly less in patients with poorer left ventricular (LV) function and more severe LV dilatation, and in those with a higher tumor necrosis factor-alpha (TNF-alpha) level. NIV was similar in all patient subgroups. There was a significant inverse correlation between the TNF-alpha plasma level and FMD (r=-0.75; P<.01). No correlation was found between the plasma levels of other neurohormones and FMD. CONCLUSIONS: FMD, but not NIV, was impaired in patients with IDC compared with control subjects. In patients, there were significant associations between FMD impairment and the severity of LV dilatation, the severity of LV systolic dysfunction, and the plasma TNF-alpha level. The strongest correlation was observed between TNF-alpha plasma level and FMD. These data suggest that TNF-alpha may be implicated in endothelial dysfunction in patients with IDC.

Arm↗

Determinant of left atrial dilation in patients with hypertrophic cardiomyopathy: a real-time 3-dimensional echocardiographic study.

To identify the determinants of left atrial (LA) dilation for patients with hypertrophic obstructive cardiomyopathy (HOCM), first we validated LA volume determination by real-time 3-dimensional echocardiography using magnetic resonance imaging in patients. Subsequently, real-time 3-dimensional echocardiography and 2-dimensional Doppler echocardiography were performed in 60 patients with HOCM and in 17 age-matched control subjects. LA volumes and left ventricular (LV) filling pressures were higher for patients with HOCM than in control subjects. By stepwise multilinear regression analysis, LV end-diastolic pressure, resting LV outflow tract pressure gradient, and LV wall thickness were significant determinants of LA dilation. However, tau, -dP/dt, LV stiffness, provokable pressure gradient, and mitral regurgitation did not have any independent relationship with LA volumes. Therefore, it is concluded that LA volume can be accurately determined by real-time 3-dimensional echocardiography; and LA dilation in patients with HOCM is related to LV filling pressure, LV outflow tract pressure gradient, and LV wall thickness.

Atrial Function, Left↗

Combination of pulsed-wave Doppler and real-time three-dimensional color Doppler echocardiography for quantifying the stroke volume in the left ventricular outflow tract.

Real-time three-dimensional (3-D) color Doppler echocardiography (RT3D) is capable of quantifying flow. However, low temporal resolution limits its application to stroke volume (SV) measurements. The aim of the present study was, therefore, to develop a reliable method to quantify SV. In animal experiments, cross-sectional images of the LV outflow tract were selected from the RT3D data to calculate peak flow rates (Q(p3D)). Conventional pulsed-wave (PW) Doppler was performed to measure the velocity-time integral (VTI) and the peak velocity (V(p)). By assuming that the flow is proportional to the velocity temporal waveform, SV was calculated as alpha x Q(p3D) x VTI/V(p), where alpha is a temporal correction factor. There was an excellent correlation between the reference flow meter and RT3D SV (mean difference = -1. 3 mL, y = 1. 05 x -2. 5, r = 0. 94, p < 0. 01). The new method allowed accurate SV estimations without any geometric assumptions of the spatial velocity distributions.

Animals↗

[Predictors of lack of clinical improvement at mid-term follow-up with cardiac resynchronization therapy].

INTRODUCTION: About 30% of all patients do not respond to cardiac resynchronization therapy for heart failure. The objective of the study was to analyze the variables that may predict the lack of response. PATIENTS AND METHOD: We analyzed the results in a series of 63 patients who received cardiac resynchronization with a biventricular device. Clinical and left ventricular function parameters were evaluated at the beginning of the study and at 6 months. Responders were defined as those who were alive, had not received a heart transplant, and who achieved more than a 10% increase in distance in the 6-minute walking test. RESULTS: Mean age was 68.3 (8) years, 51 patients (81%) were men, and NYHA functional class was III-IV in 79.4%. Mean left ventricular ejection fraction was 22.4% (6)%, QRS width was 177 (25) ms, and 77.8% were in sinus rhythm. Almost half (46%, n=29) had ischemic heart disease. At 6-month follow-up, 69.8% of the patients were responders. Ischemic heart disease, sustained monomorphic ventricular tachycardia and a degree of mitral regurgitation >II/IV before implantation were associated with lack of response. No association was found for any of the other baseline variables. Logistic regression analysis identified all three of the aforementioned variables as independent predictors of lack of response: ischemic heart disease OR=4.8, 95% CI, 1.2-18.3, P=.023; ventricular tachycardia OR=8.7, 95% CI, 1.8-41.3, P=.007; and mitral regurgitation OR=8.03, 95% CI, 1.7-37.1, P=.008. CONCLUSION: The likelihood of responding to resynchronization therapy is lower in patients with ischemic heart disease, significant mitral regurgitation, or sustained monomorphic ventricular tachycardia.

Aged↗

Comparison of left ventricular diastolic function in obstructive hypertrophic cardiomyopathy in patients undergoing percutaneous septal alcohol ablation versus surgical myotomy/myectomy.

Both percutaneous transcoronary alcohol septal reduction (ASR) and surgical myectomy are effective treatments to relieve left ventricular (LV) outflow tract obstruction in obstructive hypertrophic cardiomyopathy (HC). LV diastolic function was assessed by echocardiography in 57 patients with obstructive HC at baseline and 5 +/- 4 months after ASR (n = 37) or surgical myectomy (n = 20). LV outflow tract pressure gradient decreased from 65 +/- 40 to 23 +/- 21 mm Hg (p <0.01) after treatment. The ratio of the early-to-late peak diastolic LV inflow velocities, and the ratio of the early peak diastolic LV inflow velocity to the lateral mitral annulus early diastolic velocity determined by tissue Doppler imaging significantly decreased after the procedures (1.6 +/- 1.7 vs 1.0 +/- 0.7 and 15 +/- 8 vs 11 +/- 5, respectively), whereas LV inflow propagation velocity significantly increased (60 +/- 24 vs 71 +/- 36 cm/s). Left atrial size decreased from 29 +/- 7 to 25 +/- 6 cm(2) (p <0.05). Patients had a significant improvement in New York Heart Association functional class and in exercise performance. When comparing ASR with myectomy, no difference was found in the degree of change in any parameter of diastolic function. Thus, diastolic function indexes obtained by echocardiography changed after septal reduction interventions in patients with obstructive HC; this change was similar to that after surgical myectomy and ASR.

Adolescent↗

[Left ventricular remodeling in patients with hypertrophic obstructive cardiomyopathy treated with percutaneous alcohol septal ablation: an echocardiographic study].

INTRODUCTION: In patients with hypertrophic obstructive cardiomyopathy, obstruction in the left ventricular outflow tract may generate more hypertrophy. Our aim was to evaluate the impact of reducing ventricular outflow tract obstruction on left ventricular hypertrophy and remodeling after alcohol septal ablation. PATIENTS AND METHOD: 20 patients with hypertrophic obstructive cardiomyopathy who underwent alcohol septal ablation were included. Doppler echocardiography was performed in all patients at baseline, immediately after alcohol septal ablation, and at 3 and 12 months' follow-up. Left ventricular diameters and wall thickness and pressure gradients in the ventricular outflow tract were determined. RESULTS: Immediately after alcohol septal ablation, ventricular outflow tract pressure gradient decreased from 63.0 27.7 to 28.2 24.7 mmHg (p < 0.001), without significant changes in left ventricular dimensions. However, after 12 months we observed an increase in left ventricular end-diastolic (from 47.1 4.9 to 50.8 4.5 mm) and end-systolic diameter (from 27.1 3.0 to 33.7 4.6 mm), as well as a reduction in septal (from 19.5 4.0 to 15.5 2.7 mm) and posterior wall thickness (from 14.0 2.2 to 12.9 1.3 mm) (p < 0.01 in all cases). Left ventricular end-diastolic and end-systolic volumes increased (from 106.4 26.9 to 123.1 28.7 ml and from 50.2 17.3 to 56.7 18.3 ml, respectively, p < 0.01 in both cases), without changes in left ventricular ejection fraction. The reduction in ventricular outflow tract pressure gradient at 12 months' follow-up correlated significantly with the increase in left ventricular end-systolic diameter (r = 0.63; p < 0.01). CONCLUSIONS: In patients with hypertrophic obstructive cardiomyopathy who underwent alcohol septal ablation, relief of ventricular outflow tract obstruction is associated with an increase in left ventricular chamber diameters and volume. These findings suggest that middle- and long-term ventricular remodeling and regression of hypertrophy occur in these patients, which may contribute to their clinical improvement.

Cardiomyopathy, Hypertrophic↗

Real-time three-dimensional color doppler evaluation of the flow convergence zone for quantification of mitral regurgitation: Validation experimental animal study and initial clinical experience.

BACKGROUND: Pitfalls of the flow convergence (FC) method, including 2-dimensional imaging of the 3-dimensional (3D) geometry of the FC surface, can lead to erroneous quantification of mitral regurgitation (MR). This limitation may be mitigated by the use of real-time 3D color Doppler echocardiography (CE). Our objective was to validate a real-time 3D navigation method for MR quantification. METHODS: In 12 sheep with surgically induced chronic MR, 37 different hemodynamic conditions were studied with real-time 3DCE. Using real-time 3D navigation, the radius of the largest hemispherical FC zone was located and measured. MR volume was quantified according to the FC method after observing the shape of FC in 3D space. Aortic and mitral electromagnetic flow probes and meters were balanced against each other to determine reference MR volume. As an initial clinical application study, 22 patients with chronic MR were also studied with this real-time 3DCE-FC method. Left ventricular (LV) outflow tract automated cardiac flow measurement (Toshiba Corp, Tokyo, Japan) and real-time 3D LV stroke volume were used to quantify the reference MR volume (MR volume = 3DLV stroke volume - automated cardiac flow measurement). RESULTS: In the sheep model, a good correlation and agreement was seen between MR volume by real-time 3DCE and electromagnetic (y = 0.77x + 1.48, r = 0.87, P <.001, delta = -0.91 +/- 2.65 mL). In patients, real-time 3DCE-derived MR volume also showed a good correlation and agreement with the reference method (y = 0.89x - 0.38, r = 0.93, P <.001, delta = -4.8 +/- 7.6 mL). CONCLUSIONS: real-time 3DCE can capture the entire FC image, permitting geometrical recognition of the FC zone geometry and reliable MR quantification.

Adult↗