[show abstract][hide abstract] ABSTRACT: The small guanosine triphosphatase Rho and its target Rho-kinase have significant roles in experimental remodeling and ventricular dysfunction, but no data are available on Rho-kinase activation in patients with heart failure (HF). We hypothesized that, in patients with chronic HF, Rho-kinase in circulating leukocytes is activated and related to left ventricular (LV) remodeling and dysfunction.
Accordingly, Rho-kinase activity, assessed by the levels of phosphorylated to total myosin light chain phosphatase 1 (MYPT1-P/T) in circulating leukocytes, and echocardiographic LV function data were compared between patients with HF New York Heart Association functional class II or III due to systolic dysfunction (n = 17), healthy controls (n = 17), and hypertensive patients without HF (n = 17).
In the control subjects, mean MYPT1-P/T ratio was 1.2 ± 0.2 (it was similar in the hypertensive patients without HF), whereas in patients with HF, it was significantly increased by >100-fold (P < .001). Both MYPT1-P/T and log MYPT1-P/T ratios were inversely correlated with ejection fraction (r = -0.54, P < .03 and r = -0.86, P < .001, respectively). Furthermore, in patients with HF with LV end-diastolic diameter <60 mm, MYPT1-P/T ratio was 35.8 ± 18.1, whereas it was significantly higher in patients with LV diameter ≥60 mm (P < .05).
Rho-Kinase activity is markedly increased in patients with stable chronic HF under optimal medical treatment, and it is associated with pathologic LV remodeling and systolic dysfunction. Mechanisms of Rho-kinase activation in patients with HF, its role in the progression of the disease, and the direct effect of Rho-kinase inhibition need further investigation.
American heart journal 05/2011; 161(5):931-7. · 4.65 Impact Factor
[show abstract][hide abstract] ABSTRACT: The clinical assessment of pulmonary artery systolic pressure (PASP) by means of heart auscultation may be comparable to the measures obtained by Doppler echocardiography.
To compare PASP estimated by heart auscultation and echocardiography.
Thirty consecutive patients aged 70 ± 16 years (68% women) were evaluated prospectively, all of whom had an echocardiogram requested by their attending physician. Echocardiographic evaluation of PASP was made by tricuspid regurgitation velocity plus right a trial pressure estimate. Two trained clinicians, blinded for the clinical history and rest of physical examination, auscultated the patients. PASP was estimated from the auscultatory intensity of the pulmonary component in comparison to the aortic component of the second heart sound and its propagation towards the apex, in accordance to a pre-established algorithm. Correlation between auscultatory and echocardiographic measures of PASP was made by Pearson test. Variability between both methods and among observers was evaluated with Bland-Altman analysis.
Fifty two per cent of patients were hypertensive and 20% diabetic. Admission diagnoses were heart failure in 50% of cases, exacerbation of chronic obstructive pulmonary disease in 20%, pulmonary thromboembolism in 10% and other clinical entities in 20%. A significant correlation was found between auscultatory and echocardiographic estimation of PASP (r = 0.64, p = 0, 01). Bland-Altman analysis showed a mean difference between both determinations of 7.6 ± 7.6 mmHg. Bland-Altman analysis between both operators showed an average difference of 5.4 ± 8.4 mm Hg.
Heart auscultatory evaluation allows a precise and reproducible estimation of PASP and compares favorably with echocardiographic assessment.
Revista medica de Chile 11/2010; 138(11):1351-6. · 0.36 Impact Factor
[show abstract][hide abstract] ABSTRACT: Cardiac dyssynchrony is common in advanced heart failure (HF), but the changes in cardiac synchrony after myocardial infarction (MI) have not been adequately descríbed.
To study the relationship between cardiac synchrony and left ventricular remodeling after acute myocardial infarction.
Forty nine patients aged 59+/-10 years (77% men) with a first episode of a ST segment elevation MI, were studied. Scintigraphic left ventricular function and synchrony analyses were performed at baseline and after a six months follow-up. Determinations were compared with 33 healthy subjects.
At baseline, patients with MIhad a decreased left ventricular ejection fraction (LVEF) and significant dyssynchrony, when compared with controls. LVEF was 36.4%+/-10%, left ventricular end-diastolic volume (LVEDV) 127+/-38 mL, interventricular delay (IEV) 29+/-35 miliseconds (ms), and intraventricular delay (IAV), 234+/-89 ms. After 6 months, LVEF significantly improved (38%+/-10%, p =0.042) without significant changes in LVEDV (129+/-32 mL, p =0.97), IEV (24+/-17, p =0.96) or IAV (231+/-97, p =0.34). At baseline there were significant correlations between IAV and LVEF, and between IAV and LVEDV (r =0.48, p =0.001 and r =0.41, p =0.004, respectively). These correlations remained significant after 6 months. There was a positive correlation between IAV and LVEDV changes at six months (r =0.403, p =0.04).
The development of cardiac dyssynchrony correlates with adverse left ventricular remodeling after MI .
Revista medica de Chile 11/2009; 137(11):1457-62. · 0.36 Impact Factor
[show abstract][hide abstract] ABSTRACT: Nearly 10% of patients with an actual acute coronary syndrome (ACS) are discharged with an inadequate diagnosis.
To select clinical and laboratory predictors to identify patients with a high likelihood of ACS in the Chest Pain Unit.
Prospective evaluation of patients consulting in a Chest Pain Unit of a University Hospital. Initial assessment was standardized and included evaluation of pain characteristics, electrocardiogram and Troponin I. Independent predictors of ACS were identified with a multiple logistic regression.
In a four years period, 1,168 patients aged 62+/-23 years (69% males), were studied. After initial evaluation, 62% of the patients were admitted to the hospital for further testing and in 71% of them, a definite diagnosis of ACS was made. No events were reported by patients directly discharged from the Chest Pain Unit. Independent predictors associated with a higher likelihood of ACS were an abnormal electrocardiogram at the initial evaluation (Odds ratio (OR) 5.37, 95% confidence intervals (CI) 3.61-7.99), two or more cardiovascular risk factors (OR 2.16, 95% CI 1.21-2.84), cervical irradiation of the pain (OR 1.84, 95% CI 1.25-2.69), age over 65 years (OR 1.73, 95% CI (1.32-2.27) and a Troponin I above the upper normal limit (OR: 5.68, 95% CI 3.72-8.29).
Simple clinical findings allow an appropriate identification of patients with a high likelihood of ACS without specialized methods for myocardial ischemia detection.
Revista medica de Chile 05/2008; 136(4):442-50. · 0.36 Impact Factor
[show abstract][hide abstract] ABSTRACT: Hypokalemia (serum K+ < 3.5 mEq/1) is a potentially serious adverse effect of diuretic ingestion. We report a 27 year-old woman admitted with muscle weakness, a serum potassium of 2.0 mEq/1, metabolic alkalosis and EKG abnormalities simulating cardiac ischemia, that reverted with potassium chloride administration. She admitted high dose furosemide self-medication for edema. Glomerular filtration rate, tubular sodium reabsorption, potassium secretion, the renin-aldosterone system, total body water distribution and capillary permeability, were studied sequentially until 90 days after her admission. There was hyperactivity of the renin-aldosterone axis, reduction in extracellular and intracellular volumes, normal capillary permeability and high sodium tubular reabsorption, probably explained by a "rebound" salt retention associated with her decreased extracellular volume.
Revista medica de Chile 11/2007; 135(11):1456-62. · 0.36 Impact Factor