Influence of the elevation of the left ventricular diastolic pressure on the values of the first temporal derivative of the ventricular pressure (dP/dt)

PURPOSE: To assess the effects of the elevation of the left ventricular end-diastolic pressure (LVEDP) on the value of the 1st temporal derivative of the ventricular pressure (dP/dt). METHODS: Nineteen anesthetized dogs were studied. The dogs were mechanically ventilated and underwent thoracotomy with parasympathetic nervous system block. The LVEDP was controlled with the use of a perfusion circuit connected to the left atrium and adjusted to the height of a reservoir. The elevation of the LVEDP was achieved by a sudden increase in the height of a reservoir filled with blood. Continuous recordings of the electrocardiogram, the aortic and ventricular pressures and the dP/dt were performed. RESULTS: Elevation of the LVEDP did not result in any variation of the heart rate (167±16.0bpm, before the procedure; 167±15.5bpm, after the procedure). All the other variables assessed, including systolic blood pressure (128±18.3mmHg and 150±21.5mmHg), diastolic blood pressure (98±16.9mmHg and 115±19.8mmHg), LVEDP (5.5±2.49 and 9.3±3.60mmHg), and dP/dt (4,855 ± 1,082 mmHg/s and 5,149±1,242mmHg/s) showed significant increases following the expansion of the ventricular cavity. Although the elevation of the dP/dt was statistically significant, 6 dogs curiously showed a decrease in the values of dP/dt. CONCLUSION: Sudden elevation of the LVEDP resulted in increased values of dP/dt; however, in some dogs, this response was not uniform.

Improvement in left ventricular dysfunction after surgical correction of mitral regurgitation

OBJECTIVE: To evaluate whether left ventricular end-systolic (ESD) diameters £ 51mm in patients (pt) with severe chronic mitral regurgitation (MR) are predictors of a poor prognosis after mitral valve surgery (MVS). METHODS: Eleven pt (aged 36±13 years) were studied in the preoperative period (pre), median of 36 days; in the early postoperative period (post1), median of 9 days; and in the late postoperative period (post2), mean of 38.5±37.6 months. Clinical and echocardiographic data were gathered from each pt with MR and systolic diameter ³51mm (mean = 57±4mm) to evaluate the result of MVS. Ten patients were in NYHA Class III/IV. RESULTS: All but 2 pt improved in functional class. Two pt died from heart failure and infectious endocarditis 14 and 11 months, respectively, after valve replacement. According to ejection fraction (EF) in post2, we identified 2 groups: group 1 (n=6), whose EF decreased in post1, but increased in post2 (p=0.01) and group 2 (n=5), whose EF decreased progressively from post1 to post2 (p=0.10). All pt with symptoms lasting £ 48 months had improvement in EF in post2 (p=0.01). CONCLUSION: ESD ³51mm are not always associated with a poor prognosis after MVS in patients with MR. Symptoms lasting up to 48 months are associated with improvement in left ventricular function.

Impact of Atrial Fibrillation Ablation on Left Ventricular Filling Pressure and Left Atrial Remodeling

Background:Left ventricular (LV) diastolic dysfunction is associated with new-onset atrial fibrillation (AF), and the estimation of elevated LV filling pressures by E/e' ratio is related to worse outcomes in patients with AF. However, it is unknown if restoring sinus rhythm reverses this process.Objective:To evaluate the impact of AF ablation on estimated LV filling pressure.Methods:A total of 141 patients underwent radiofrequency (RF) ablation to treat drug-refractory AF. Transthoracic echocardiography was performed 30 days before and 12 months after ablation. LV functional parameters, left atrial volume index (LAVind), and transmitral pulsed and mitral annulus tissue Doppler (e' and E/e') were assessed. Paroxysmal AF was present in 18 patients, persistent AF was present in 102 patients, and long-standing persistent AF in 21 patients. Follow-up included electrocardiographic examination and 24-h Holter monitoring at 3, 6, and 12 months after ablation.Results:One hundred seventeen patients (82.9%) were free of AF during the follow-up (average, 18 ± 5 months). LAVind reduced in the successful group (30.2 mL/m2 ± 10.6 mL/m2 to 22.6 mL/m2 ± 1.1 mL/m2, p < 0.001) compared to the non-successful group (37.7 mL/m2 ± 14.3 mL/m2 to 37.5 mL/m2 ± 14.5 mL/m2, p = ns). Improvement of LV filling pressure assessed by a reduction in the E/e' ratio was observed only after successful ablation (11.5 ± 4.5 vs. 7.1 ± 3.7, p < 0.001) but not in patients with recurrent AF (12.7 ± 4.4 vs. 12 ± 3.3, p = ns). The success rate was lower in the long-standing persistent AF patient group (57% vs. 87%, p = 0.001).Conclusion:Successful AF ablation is associated with LA reverse remodeling and an improvement in LV filling pressure.

Methodological Gaps in Left Atrial Function Assessment by 2D Speckle Tracking Echocardiography

Abstract The assessment of left atrial (LA) function is used in various cardiovascular diseases. LA plays a complementary role in cardiac performance by modulating left ventricular (LV) function. Transthoracic two-dimensional (2D) phasic volumes and Doppler echocardiography can measure LA function non‑invasively. However, evaluation of LA deformation derived from 2D speckle tracking echocardiography (STE) is a new feasible and promising approach for assessment of LA mechanics. These parameters are able to detect subclinical LA dysfunction in different pathological condition. Normal ranges for LA deformation and cut-off values to diagnose LA dysfunction with different diseases have been reported, but data are still conflicting, probably because of some methodological and technical issues. This review highlights the importance of an unique standardized technique to assess the LA phasic functions by STE, and discusses recent studies on the most important clinical applications of this technique.

Clinical use of temporary percutaneous left ventricular assist devices.

Background: Temporary percutaneous left ventricular assist devices (TPLVAD) can be inserted and removed in awake patients. They substitute left ventricular function for a period of up to a few weeks and provide an excellent backup and bridge to recovery or decision. Methods: Retrospective analysis of 75 patients who received TPLVAD to treat cardiogenic shock (n = 49) or to facilitate high-risk percutaneous coronary intervention (PCI) (n = 26). Forty-two patients with cardiogenic shock and 16 patients with high-risk PCI received a TandemHeart and 7 patients and 10 patients, respectively, received an Impella Recover LP 2.5. Outcome and related complications up to 1 month are reported with reference to device depending function. Results: One-month survival was 53% in patients with shock and 96% in patients with PCI. Conclusion: TPLVADs can support the failing heart with acceptable risk. Outcome is better in prophylactic use than in patients with cardiogenic shock. (C) 2011 Wiley-Liss, Inc.

Prevalence of left ventricular regional dysfunction in arrhythmogenic right ventricular dysplasia: a tagged MRI study.

BACKGROUND: Although arrhythmogenic right ventricular dysplasia (ARVD) predominantly affects the right ventricle (RV), genetic/molecular and histological changes are biventricular. Regional left ventricular (LV) function has not been systematically studied in ARVD. METHODS AND RESULTS: The study population included 21 patients with suspected ARVD who underwent evaluation with MRI including tagging. Eleven healthy volunteers served as control subjects. Peak systolic regional circumferential strain (Ecc, %) was calculated by harmonic phase from tagged MRI based on the 16-segment model. Patients who met ARVD Task Force criteria were classified as definite ARVD, whereas patients with a positive family history who had 1 additional minor criterion and patients without a family history with 1 major or 2 minor criteria were classified as probable ARVD. Of the 21 ARVD subjects, 11 had definite ARVD and 10 had probable ARVD. Compared with control subjects, probable ARVD patients had similar RV ejection fraction (58.9+/-6.2% versus 53.5+/-7.6%, P=0.20), but definite ARVD patients had significantly reduced RV ejection fraction (58.9+/-6.2% versus 45.2+/-6.0%, P=0.001). LV ejection fraction was similar in all 3 groups. Compared with control subjects, peak systolic Ecc was significantly less negative in 6 of 16 (37.5%) segments in definite ARVD and 3 of 16 segments (18.7%) in probable ARVD (all P<0.05). CONCLUSIONS: ARVD is associated with regional LV dysfunction, which appears to parallel degree of RV dysfunction. Further large studies are needed to validate this finding and to better define implications of subclinical segmental LV dysfunction.

Automated grading of left ventricular segmental wall motion by an artificial neural network using color kinesis images

The present study describes an auxiliary tool in the diagnosis of left ventricular (LV) segmental wall motion (WM) abnormalities based on color-coded echocardiographic WM images. An artificial neural network (ANN) was developed and validated for grading LV segmental WM using data from color kinesis (CK) images, a technique developed to display the timing and magnitude of global and regional WM in real time. We evaluated 21 normal subjects and 20 patients with LVWM abnormalities revealed by two-dimensional echocardiography. CK images were obtained in two sets of viewing planes. A method was developed to analyze CK images, providing quantitation of fractional area change in each of the 16 LV segments. Two experienced observers analyzed LVWM from two-dimensional images and scored them as: 1) normal, 2) mild hypokinesia, 3) moderate hypokinesia, 4) severe hypokinesia, 5) akinesia, and 6) dyskinesia. Based on expert analysis of 10 normal subjects and 10 patients, we trained a multilayer perceptron ANN using a back-propagation algorithm to provide automated grading of LVWM, and this ANN was then tested in the remaining subjects. Excellent concordance between expert and ANN analysis was shown by ROC curve analysis, with measured area under the curve of 0.975. An excellent correlation was also obtained for global LV segmental WM index by expert and ANN analysis (R² = 0.99). In conclusion, ANN showed high accuracy for automated semi-quantitative grading of WM based on CK images. This technique can be an important aid, improving diagnostic accuracy and reducing inter-observer variability in scoring segmental LVWM.

Tobacco smoke-induced left ventricular remodelling is not associated with metalloproteinase-2 or -9 activation

Aim: To investigate the role of MMP-2 and MMP-9 in cardiac remodelling induced by tobacco smoke exposure in rats.Methods: Rats were allocated into two groups: C (n = 9): control animals; ETS (n = 9): exposed to tobacco smoke. After 4months, the animals underwent echocardiography, morphometric study and determination of MMP-2 and MMP-9 activity.Results: ETS rats had larger diastolic (C= 15.6 +/- 1.2 mm/kg, ETS = 18.0 +/- 0.9 mm/kg; p < 0.001) and systolic (C= 7.3 +/- 1.2 mm/kg, ETS = 9.2 0.9 mm/kg; p = 0.001) ventricular diameters adjusted for body weight. Fractional shortening (C= 53 +/- 4.8%, ETS = 48 +/- 3.3%; p = 0.031) and ejection fraction (C= 0. 89 +/- 0.03 5 ETS = 0. 86 +/- 0.02; p = 0.03 0) were smaller in the ETS group. Myocyte cross-sectional area (C= 245 8 mu m(2), ETS=253 8 mu m(2); p = 0.028) was higher in ETS rats. There were no differences in MNtP-2 (C=50 +/- 14%; ETS 43 +/- 11%, p 0.22 +/- 8) or MMP-9 (C=0.36 +/- 0.3%; ETS=0.62 +/- 0.3%, p=0.630) activity between the groups.Conclusion: MMP-2 and MMP-9 did not participate in the remodelling process induced by tobacco smoke exposure. (c) 2007 European Society of Cardiology. Published by Elsevier B.V. All rights reserved.

Influence of the elevation of the left ventricular diastolic pressure on the values of the first temporal derivative of the ventricular pressure (dP/dt)

PURPOSE: To assess the effects of the elevation of the left ventricular end-diastolic pressure (LVEDP) on the value of the 1st temporal derivative of the ventricular pressure (dP/dt). METHODS: Nineteen anesthetized dogs were studied. The dogs were mechanically ventilated and underwent thoracotomy with parasympathetic nervous system block. The LVEDP was controlled with the use of a perfusion circuit connected to the left atrium and adjusted to the height of a reservoir. The elevation of the LVEDP was achieved by a sudden increase in the height of a reservoir filled with blood. Continuous recordings of the electrocardiogram, the aortic and ventricular pressures and the dP/dt were performed. RESULTS: Elevation of the LVEDP did not result in any variation of the heart rate (167±16.0bpm, before the procedure; 167±15.5bpm, after the procedure). All the other variables assessed, including systolic blood pressure (128±18.3mmHg and 150±21.5mmHg), diastolic blood pressure (98±16.9mmHg and 115±19.8mmHg), LVEDP (5.5±2.49 and 9.3±3.60mmHg), and dP/dt (4,855 ± 1,082 mmHg/s and 5,149±1,242mmHg/s) showed significant increases following the expansion of the ventricular cavity. Although the elevation of the dP/dt was statistically significant, 6 dogs curiously showed a decrease in the values of dP/dt. CONCLUSION: Sudden elevation of the LVEDP resulted in increased values of dP/dt; however, in some dogs, this response was not uniform.

GROWTH HORMONE ATTENUATES MYOCARDIAL FIBROSIS IN RATS WITH CHRONIC PRESSURE OVERLOAD-INDUCED LEFT VENTRICULAR HYPERTROPHY

1. The role of growth hormone (GH) in cardiac remodelling and function in chronic and persistent pressure overload-induced left ventricular hypertrophy has not been defined. The aim of the present study was to assess short-term GH treatment on left ventricular function and remodelling in rats with chronic pressure overload-induced hypertrophy.2. Twenty-six weeks after induction of ascending aortic stenosis (AAS), rats were treated with daily subcutaneous injections of recombinant human GH (1 mg/kg per day; AAS-GH group) or saline (AAS-P group) for 14 days. Sham-operated animals served as controls. Left ventricular function was assessed by echocardiography before and after GH treatment. Myocardial fibrosis was evaluated by histological analysis.3. Before GH treatment, AAS rats presented similar left ventricular function and structure. Treatment of rats with GH after the AAS procedure did not change bodyweight or heart weight, both of which were higher in the AAS groups than in the controls. After GH treatment, posterior wall shortening velocity (PWSV) was lower in the AAS-P group than in the control group. However, in the AAS-GH group, PWSV was between that in the control and AAS-P groups and did not differ significantly from either group. Fractional collagen (% of total area) was significantly higher in the AAS-P and AAS-GH groups compared with control (10.34 +/- 1.29, 4.44 +/- 1.37 and 1.88 +/- 0.88%, respectively; P < 0.05) and was higher still in the AAS-P group compared with the AAS-GH group.4. The present study has shown that short-term administration of GH to rats with chronic pressure overload-induced left ventricular hypertrophy induces cardioprotection by attenuating myocardial fibrosis.

Reduction of diameter of the left ventricle of dogs by plication of the left ventricular free wall

Objective - To determine effects of reducing the diameter of the left ventricle of dogs by plication of the left ventricular free wall. Animals - 8 healthy adult mixed-breed dogs. Procedure - Left lateral thoracotomy and a T-shaped pericardiotomy were performed. The free wall of the left ventricle was imbricated with 3 interrupted transfixing sutures applied in a horizontal mattress pattern, using 3-0 polypropylene suture assembled on a straight cutting needle. Surgeons were careful to avoid the coronary vessels. Echocardiography was performed 24 hours before and 48 hours after surgery. Electrocardiography was performed before and 1, 2, 7, 15, 21, 30, and 60 days after surgery. Results - Echocardiographic measurements revealed that the diameter of the left ventricle was reduced by a mean of 23.5%. Electrocardiography revealed ventricular premature complexes 24 hours after surgery that regressed without treatment during the first week after surgery. Conclusions and Clinical Relevance - Plication of the left ventricular free wall of dogs can reduce end-diastolic and end-systolic dimensions of the left ventricle. The technique is simple and does not require cardiopulmonary bypass. According to Laplace's law, the reduction of cardiac diameter leads to reduction on free-wall tension and may improve left ventricular function in dilatated hearts. Thus, additional studies involving dogs with dilated cardiomyopathy should be conducted.

Clinical outcome of high-risk patients with severe aortic stenosis and reduced left ventricular ejection fraction undergoing medical treatment or TAVI

Introduction Reduced left ventricular function in patients with severe symptomatic valvular aortic stenosis is associated with impaired clinical outcome in patients undergoing surgical aortic valve replacement (SAVR). Transcatheter Aortic Valve Implantation (TAVI) has been shown non-inferior to SAVR in high-risk patients with respect to mortality and may result in faster left ventricular recovery. Methods We investigated clinical outcomes of high-risk patients with severe aortic stenosis undergoing medical treatment (n = 71) or TAVI (n = 256) stratified by left ventricular ejection fraction (LVEF) in a prospective single center registry. Results Twenty-five patients (35%) among the medical cohort were found to have an LVEF≤30% (mean 26.7±4.1%) and 37 patients (14%) among the TAVI patients (mean 25.2±4.4%). Estimated peri-interventional risk as assessed by logistic EuroSCORE was significantly higher in patients with severely impaired LVEF as compared to patients with LVEF>30% (medical/TAVI 38.5±13.8%/40.6±16.4% versus medical/TAVI 22.5±10.8%/22.1±12.8%, p <0.001). In patients undergoing TAVI, there was no significant difference in the combined endpoint of death, myocardial infarction, major stroke, life-threatening bleeding, major access-site complications, valvular re-intervention, or renal failure at 30 days between the two groups (21.0% versus 27.0%, p = 0.40). After TAVI, patients with LVEF≤30% experienced a rapid improvement in LVEF (from 25±4% to 34±10% at discharge, p = 0.002) associated with improved NYHA functional class at 30 days (decrease ≥1 NYHA class in 95%). During long-term follow-up no difference in survival was observed in patients undergoing TAVI irrespective of baseline LVEF (p = 0.29), whereas there was a significantly higher mortality in medically treated patients with severely reduced LVEF (log rank p = 0.001). Conclusion TAVI in patients with severely reduced left ventricular function may be performed safely and is associated with rapid recovery of systolic left ventricular function and heart failure symptoms.

Clinical use of temporary percutaneous left ventricular assist devices

Temporary percutaneous left ventricular assist devices (TPLVAD) can be inserted and removed in awake patients. They substitute left ventricular function for a period of up to a few weeks and provide an excellent backup and bridge to recovery or decision.

Eosinophilic heart: Marked left ventricular wall thickening and myocardial dysfunction improving with corticosteroid therapy

We report a case of a 34-year-old male with acute severe heart failure associated with marked concentric left ventricular wall thickening and biopsy evidence of eosinophilic myocardial infiltrate. This appears to be an unusual description of this degree of concentric myocardial thickening in eosinophilic myocarditis coupled with Doppler tissue echocardiography. Following high-dose corticosteroid treatment, wall thickness, systolic and diastolic left ventricular function normalized and the patient experienced a dramatic clinical improvement. (ECHOCARDIOGRAPHY, Volume 20, May 2003).

Sustained Ventricular Tachycardia Is Associated with Regional Myocardial Sympathetic Denervation Assessed with (123)I-Metaiodobenzylguanidine in Chronic Chagas Cardiomyopathy

Cardiac sympathetic denervation and ventricular arrhythmia are frequently observed in chronic Chagas cardiomyopathy (CCC). This study quantitatively evaluated the association between cardiac sympathetic denervation and sustained ventricular tachycardia (SVT) in patients with CCC. Methods: We prospectively investigated patients with CCC and left ventricular ejection fraction (LVEF) greater than 35% with SVT (SVT group: n = 5 15; mean age +/- SD, 61 +/- 8 y; LVEF, 51% +/- 8%) and patients without SVT (non-SVT group: n = 11; mean age +/- SD, 55 +/- 10 y; LVEF, 57% +/- 10%). Patients underwent myocardial scintigraphy with (123)I-metaiodobenzylguanidine ((123)I-MIBG) for the evaluation of sympathetic innervation and resting perfusion with (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) for the evaluation of myocardial viability. A visual semiquantitative score was attributed for regional uptake of each radiotracer using a 17-segment left ventricular segmentation model (0, normal; 4, absence of uptake). A mismatch defect was defined as occurring in segments with a 99mTc-MIBI uptake score of 0 or 1 and a (123)I-MIBG score of 2 or more. Results: Compared with the non-SVT group, the SVT group had a similar (99m)Tc-MIBI summed score (6.9 +/- 7.5 vs. 4.4 +/- 5.2, respectively, P = 0.69) but a higher (123)I-MIBG summed score (10.9 +/- 7.8 vs. 22.4 +/- 9.5, respectively, P = 0.007) and a higher number of mismatch defects per patient (2.0 +/- 2.2 vs. 7.1 +/- 2.0, respectively, P < 0.0001). The presence of more than 3 mismatch defects was strongly associated with the presence of SVT (93% sensitivity, 82% specificity; P = 0.0002). Conclusion: In CCC, the amount of sympathetically denervated viable myocardium is associated with the occurrence of SVT. Myocardial sympathetic denervation may participate in triggering malignant ventricular arrhythmia in CCC patients with relatively well-preserved ventricular function.