Abstract Background Intraventricular fluid dynamics can be assessed clinically using imaging. The contribution of vortex structures to left ventricular (LV) diastolic function has never been ...quantified in vivo. Objectives This study sought to understand the impact of intraventricular flow patterns on filling and to assess whether impaired fluid dynamics may be a source of diastolic dysfunction. Methods Two-dimensional flow velocity fields from color Doppler echocardiographic sequences were obtained in 20 patients with nonischemic dilated cardiomyopathy (NIDCM), 20 patients with hypertrophic cardiomyopathy (HCM), and 20 control healthy volunteers. Using a flow decomposition method, we isolated the rotational velocity generated by the vortex ring from the surrounding flow in the left ventricle. Results The vortex was responsible for entering 13 ± 6% of filling volume in the control group and 19 ± 8% in the NIDCM group (p = 0.004), but only 5 ± 5% in the HCM group (p < 0.0001 vs. controls). Favorable vortical effects on intraventricular pressure gradients were observed in the control and NIDCM groups but not in HCM patients. Differences in chamber sphericity explained variations in the vortex contribution to filling between groups (p < 0.005). Conclusions The diastolic vortex is responsible for entering a significant fraction of LV filling volume at no energetic or pressure cost. Thus, intraventricular fluid mechanics are an important determinant of global chamber LV operative stiffness. Reduced stiffness in NIDCM is partially related to enhanced vorticity. Conversely, impaired vortex generation is an unreported mechanism of diastolic dysfunction in HCM and probably other causes of concentric remodeling.
Echocardiography is the key tool for the diagnosis and evaluation of aortic stenosis. Because clinical decision-making is based on the echocardiographic assessment of its severity, it is essential ...that standards are adopted to maintain accuracy and consistency across echocardiographic laboratories. Detailed recommendations for the echocardiographic assessment of valve stenosis were published by the European Association of Echocardiography and the American Society of Echocardiography in 2009. In the meantime, numerous new studies on aortic stenosis have been published with particular new insights into the difficult subgroup of low gradient aortic stenosis making an update of recommendations necessary. The document focuses in particular on the optimization of left ventricular outflow tract assessment, low flow, low gradient aortic stenosis with preserved ejection fraction, a new classification of aortic stenosis by gradient, flow and ejection fraction, and a grading algorithm for an integrated and stepwise approach of aortic stenosis assessment in clinical practice.
Abstract Purpose The aims were to analyze the temporal evolution of neutrophil apoptosis, to determine the differences in neutrophil apoptosis among 28-day survivors and nonsurvivors, and to evaluate ...the use of neutrophil apoptosis as a predictor of mortality in patients with septic shock. Materials and Methods Prospective multicenter observational study carried out between July 2006 and June 2009. The staining solution study included 80 patients with septic shock and 25 healthy volunteers. Neutrophil apoptosis was assessed by fluorescein isothiocyanate (FITC)–conjugated annexin V and aminoactinomycin D staining. Results The percentage of neutrophil apoptosis was significantly decreased at 24 hours, 5 days, and 12 days after the diagnosis of septic shock (14.8% ± 13.4%, 13.4% ± 8.4%, and 15.4% ± 12.8%, respectively; P < .0001) compared with the control group (37.6% ± 12.8%). The difference in apoptosis between 28-day surviving and nonsurviving patients was nonsignificant ( P > .05). The mortality rate at 28 days was 53.7%. The crude hazard ratio for mortality in patients with septic shock did not differ according to the percentage of apoptosis (hazard ratio, 1.006; 95% confidence interval, 0.98-1.03; P = .60). Conclusions During the first 12 days of septic shock development, the level of neutrophil apoptosis decreases and does not recover normal values. No differences were observed between surviving and nonsurviving patients.
Conduction channels and electrograms with isolated component/late potentials are sensitive markers of the substrate of post–myocardial infarction sustained monomorphic ventricular tachycardia (VT). ...Ablation of all conduction channels and isolated component/late potentials (complete endocardial VT substrate ablation CEVTSA) during sinus rhythm could simplify and facilitate the ablation procedure, mainly in patients without references for clinical VT substrate identification. The aim of this study was to assess the safety, efficacy, and predictors of VT recurrence after CEVTSA. Electroanatomic mapping and CEVTSA were performed in 59 post–myocardial infarction patients (mean age 67 ± 9 years, mean left ventricular ejection fraction 30 ± 11%), 24 of whom did not have clinical VT substrate references. The mean areas of scar (≤1.5 mV) and dense scar (≤0.5 mV) were 76 ± 42 and 34 ± 24 cm2 , respectively; isolated component/late potentials and conduction channels were identified and ablated in 97% and 83% of patients (mean ablation area 14 ± 10 cm2 ). No life-threatening complications occurred during the procedure. After 1 year and at the end of follow-up (mean 39 ± 21 months), 81% and 58% of patients were free of VT. No differences were observed between patients with and without specific clinical VT substrate identification. Univariate analysis identified the left ventricular ejection fraction, VT cycle length (VTCL), infarct location (inferior vs anterior), and dense scar area as predictors of VT recurrence, and Cox analysis identified VTCL (hazard ratio 0.42, p <0.001) and dense scar area (hazard ratio 2.65, p <0.0006) as independent predictors. No patients with dense scar area ≤25 cm2 and VTCL >350 ms had recurrences. In conclusion, CEVTSA is safe and effective, even in patients without clinical VT substrate identification. Scar area and VTCL are valuable predictors of VT recurrence.
Abstract Purpose Ventilator-associated pneumonia (VAP) is the main infectious complication in cardiac surgery patients and is associated with an important increase in morbidity and mortality. The aim ...of our study was to analyze the impact of VAP on mortality excluding other comorbidities and to study its etiology and the risk factors for its development. Materials and Methods This prospective cohort study included 1610 postoperative cardiac surgery patients' status post cardiopulmonary bypass (CPB) between July 2004 and January 2008. The primary outcome measures were the development of VAP and in-hospital mortality. Results Ventilator-associated pneumonia was observed in 124 patients (7.7%). Patients with VAP had a longer length of hospitalization (40.7 ± 35.1 vs 16.1 ± 30.1 days, P < .0001) and greater in-hospital mortality (49.2% 61/124 vs 2.0% 30/1486, P = .0001) in comparison with patients without VAP. After performing the Cox multivariant analysis adjustment, VAP was identified as the most important independent mortality risk factor (adjusted hazard ratio HR, 8.53; 95% confidence interval, 4.21-17.30; P = .0001). Other independent risk factors of in-hospital mortality were chronic renal failure (HR, 2.56), diabetes mellitus (HR, 1.90), CPB time (HR, 1.51), respiratory failure (HR, 2.13), acute renal failure (HR, 2.39), and mediastinal bleeding of at least 1000 mL (HR, 1.81). Conclusions The development of VAP after CPB is the most important independent risk factor for in-hospital mortality. Identification of effective strategies for the prevention of VAP is needed.
Endo-epicardial substrate ablation reduces ventricular tachycardia (VT) recurrences; however, not all patients in whom the epicardium is explored have a VT substrate. Contrast-enhanced magnetic ...resonance imaging (ceMRI) is used to characterize VT substrate after myocardial infarction.
The purpose of this study was to determine if epicardial VT substrate can be identified noninvasively by ceMRI-based endo-epicardial signal intensity (SI) mapping.
Myocardial infarction was induced in 31 pigs. Four or 16 weeks later, ceMRI was obtained, and the averaged subendocardial and subepicardial SIs were projected onto 3-dimensional endocardial and epicardial shells in which dense scar, heterogeneous tissue (HT), and normal tissue were differentiated. An HT channel was defined as a corridor of HT surrounded by dense scar and connected to normal tissue. A "patchy" scar pattern was defined as the presence of at least 3 dense scar islets surrounded by HT forming ≥2 HT channels. Electrophysiologic study was performed after ceMRI.
Thirty-three different sustained monomorphic VTs (291 ± 49 ms) were induced in 25 pigs. Mid-diastolic electrograms were recorded in the endocardium (endocardial VT) in 17 and in the epicardium (epicardial VT) in 13. Epicardial SI mapping showed that scar area was similar in animals with and without epicardial VT (24 ± 6 cm2 vs. 25 ± 12 cm2), but HT covered a higher surface of the epicardial scar in animals with VT (76 ± 6% vs. 61 ± 10%, P = .03). A patchy scar pattern was observed in all animals with epicardial VT but only in 3 animals without VT (P < .001).
CeMRI-based SI mapping allows identification of the epicardial VT substrate.
Abstract Objectives The goal of this study was to determine the functional impact of paradoxical low-gradient aortic stenosis (PLGAS) and clarify whether the relevance of the valvular obstruction is ...related to baseline flow. Background Establishing the significance of PLGAS is particularly challenging. Methods Twenty symptomatic patients (77 ± 6 years of age; 17 female subjects) with PLGAS (mean gradient 28 ± 6 mm Hg; aortic valve area 0.8 ± 0.1 cm2 ; ejection fraction 66 ± 7%) underwent cardiopulmonary exercise testing combined with right-heart catheterization and Doppler echocardiographic measurements. Results Aortic valve area increased by 84 ± 23% (p < 0.001) and, in 70% of subjects, it reached values >1.0 cm2 at peak exercise. Stroke volume index and blood pressure increased by 83 ± 56% and 26 ± 16%, respectively (both p < 0.0001). Peak oxygen consumption inversely correlated with the rate of increase in pulmonary capillary wedge pressure (PCWP) (PCWP slope: R = –0.61; p = 0.004). In turn, the PCWP slope was determined by changes in the valvular and vascular load but not by the rest of the indices of aortic stenosis. The functional impact of PLGAS was also not related to baseline flow. Agreement between Doppler echocardiography and the Fick technique was good up to intermediate workload. Conclusions In symptomatic patients with PLGAS, the capacity to dynamically reduce vascular and valvular loads determines the effect of exercise on PCWP, which, in turn, conditions the functional status. A critically fixed valvular obstruction may not be the main mechanism of functional impairment in a large proportion of patients with PLGAS. Exercise echocardiography is suitable to study the dynamics of PLGAS.
Abstract Objectives The aim of this study was to determine if noninvasive measurement of scar by contrast-enhanced magnetic resonance imaging (MRI)–based signal intensity (SI) mapping predicts ...ventricular tachycardia (VT) recurrence after endocardial ablation. Background Scar extension on voltage mapping predicts VT recurrence after ablation procedures. Methods A total of 46 consecutive patients with previous myocardial infarction (87% men, mean age 68 ± 9 years, mean left ventricular ejection fraction 36 ± 10%) who underwent VT substrate ablation before the implantation of a cardioverter-defibrillator were included. Before ablation, contrast-enhanced MRI was performed, and areas of endocardial and epicardial scarring and heterogeneous tissue were measured; averaged subendocardial and subepicardial signal intensities were projected onto 3-dimensional endocardial and epicardial shells in which dense scar, heterogeneous tissue, and normal tissue were differentiated. Results During a mean follow-up period of 32 ± 24 months 17 patients (37%) had VT recurrence. Patients with recurrence had larger scar and heterogeneous tissue areas on SI maps in both endocardium (81 ± 27 cm2 vs. 48 ± 21 cm2 p = 0.001 and 53 ± 21 cm2 vs. 30 ± 15 cm2 p = 0.001, respectively) and epicardium (76 ± 28 cm2 vs. 51 ± 29 cm2 p = 0.032 and 59 ± 25 cm2 vs. 37 ± 19 cm2 p = 0.008). In the multivariate analysis, MRI endocardial scar extension was the only independent predictor of VT recurrence (hazard ratio: 1.310 per 10 cm2 ; 95% confidence interval: 1.051 to 1.632; p = 0.034). Freedom from VT recurrence was higher in patients with small endocardial scars by MRI (<65 cm2 ) than in those with larger scars (≥65 cm2 ) (85% vs. 20%, log-rank p = 0.018). Conclusions Pre-procedure endocardial scar extension assessment by contrast-enhanced MRI predicts VT recurrence after endocardial substrate ablation. This information may be useful to select patients for ablation procedures.
Conventional diagnostic tests in allergy are insufficient to clarify the origin of vernal conjunctivitis (VC).
To evaluate IgE-mediated hypersensitivity by component-resolved diagnosis (CRD) in tears ...and serum from patients with VC and to evaluate how to treat patients with identified triggering allergens by specific immunotherapy.
Patients were divided into 3 groups: (1) patients with VC (25 patients), (2) patients allergic to grass pollen with seasonal allergic conjunctivitis (AC) (50 patients), and (3) healthy blood donors (50 patients). If triggering allergens were detected, specific conventional immunotherapy was administered for 1 year.
Twenty-five patients with VC were evaluated. The identified triggering allergens were n Lol p 1 (11 patients), n Cyn d 1 (8 patients), group 4 and 6 grasses (6 patients), and group 5 grasses (5 patients). Prick test and pollen IgE test results were positive in one patient. Clinical improvement was observed in 13 of the 25 patients with VC after 1 year of specific immunotherapy.
CRD seems to be a more sensitive diagnostic tool compared with prick test and IgE detection. Specific CRD-led immunotherapy may achieve clinical improvements in patients with VC.
Abstract Background Systemic arterial load impacts the symptomatic status and outcome of patients with calcific degenerative aortic stenosis (AS). However, assessing vascular properties is ...challenging because the arterial tree’s behavior could be influenced by the valvular obstruction. Objectives This study sought to characterize the interaction between valvular and vascular functions in patients with AS by using transcatheter aortic valve replacement (TAVR) as a clinical model of isolated intervention. Methods Aortic pressure and flow were measured simultaneously using high-fidelity sensors in 23 patients (mean 79 ± 7 years of age) before and after TAVR. Blood pressure and clinical response were registered at 6-month follow-up. Results Systolic and pulse arterial pressures, as well as indices of vascular function (vascular resistance, aortic input impedance, compliance, and arterial elastance), were significantly modified by TAVR, exhibiting stiffer vascular behavior post-intervention (all, p < 0.05). Peak left ventricular pressure decreased after TAVR (186 ± 36 mm Hg vs. 162 ± 23 mm Hg, respectively; p = 0.003) but remained at >140 mm Hg in 70% of patients. Wave intensity analysis showed abnormally low forward and backward compression waves at baseline, increasing significantly after TAVR. Stroke volume decreased (−21 ± 19%; p < 0.001) and correlated with continuous and pulsatile indices of arterial load. In the 48 h following TAVR, a hypertensive response was observed in 12 patients (52%), and after 6-month follow-up, 5 patients required further intensification of discharge antihypertensive therapy. Conclusions Vascular function in calcific degenerative AS is conditioned by the upstream valvular obstruction that dampens forward and backward compression waves in the arterial tree. An increase in vascular load after TAVR limits the procedure’s acute afterload relief.
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