Diego Castini

Effects of preload reduction on mitral flow velocity pattern in normal subjects

In the last few years, alterations in transmitral diastolic flow pattern have been used to assess changes in left ventricular diastolic properties. However, since diastolic flow primarily reflects the atrioventricular pressure gradient, loading conditions, as well as intrinsic left ventricular properties, should be able to affect this pattern. This study was selectively designed to decrease preload (a major determinant of the atrioventricular pressure gradient) in normal subjects to observe the effects on the Doppler transmitral flow pattern without pharmacologic interventions that may also affect left ventricular diastolic properties. In 12 normal subjects, preload was reduced by inflation of blood pressure cuffs placed at the level of the root of the 4 limbs. The peak velocity of early mitral flow (E wave) decreased from 62 +/- 8 to 51 +/- 7 cm/s (p less than 0.001), while no changes were found in the maximal velocity after atrial contraction; this caused a significant decrease in the ratio of these 2 velocities (the E to A ratio) from 1.5 +/- 0.3 to 1.1 +/- 0.1 (p less than 0.001). The time-velocity integral of early diastolic inflow decreased from 7.8 +/- 1.3 to 6.1 +/- 1.3 cm (p less than 0.001) with no significant changes of the time-velocity integral of inflow after atrial contraction. Therefore, preload reduction in normal subjects significantly reduces transmitral flow in early diastole with preserved late ventricular filling, producing a pattern that can mimic the changes previously described in left ventricular diastolic dysfunction.

Effects of infusion of glucose-insulin-potassium on myocardial function after a recent myocardial infarction.

We studied the effects of glucose, insulin, and KCI infusion (GIK), on regional myocardial perfusion and function by 99m-Tc-tetrofosmin-gated SPECT. Methods - we studied 21 male patients with their first uncomplicated acute myocardial infarction (AMI). All patients underwent a rest and submaximal stress perfusion study before and after 24-hour infusion of GIK-solution (group A) or saline solution (group B). Results - Group A showed better stress tolerance and ischaemic threshold improvement after GIK infusion whilst no statistical differences were found between basal and post-infusion test in group B. At first the stress test in group A, of the 192 segments analysed, 52 (27%) showed reversible perfusion defect. In group B, of 144 segments analysed, 31 (21%) showed reversible perfusion defect. A postinfusion analysis in group A showed a post-GIK end-diastolic significant count improvement in 21 segments, and a post-GIK end-systolic count improvement in 22 segments. In group B, perfusion increase was observed only in 4 segments, whilst systolic thickening increase was observed only in I segment. Conclusion - these data demonstrate the efficacy of GIK infusion to improve regional myocardial perfusion and function mainly in segments adjacent to the recently infarcted area.

Prevention of Contrast‐induced Nephropathy: A Single Center Randomized Study

Contrast‐induced nephropathy (CIN) is the third cause of acute deterioration of renal function in hospitalized patients.

A comparison between two different definitions of contrast-induced acute kidney injury in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

BACKGROUND Contrast-induced acute kidney injury (CI-AKI) is associated with significantly increased mortality after primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI). The prognostic value of CI-AKI depends on the definitions used to define it. We compare the predictive accuracy of long-term mortality of two definitions of CI-AKI on consecutive patients undergoing pPCI for STEMI. METHODS Incidence, risk factors and long-term prognosis of CI-AKI were assessed according to two different definitions: the first as an increase in serum creatinine ≥ 25% or ≥ 0.5 mg/dl from baseline within 72 h after pPCI (contrast-induced nephropathy (CIN) criteria), the second one according to Acute Kidney Injury Network (AKIN) classification system. RESULTS A total of 402 patients were enrolled. The median follow-up period was 12 ± 4 months. Long-term mortality rate was 9.5%. Independent predictors of long-term mortality were: older age, basal renal impairment, left ventricular ejection fraction <40%, in-hospital major bleedings and CI-AKI. A significant correlation was found between mortality and CI-AKI as assessed by both CIN (HR 4.84, 95% CI: 2.56-9.16, p=0.000) and AKIN (HR 9.70, 95% CI: 5.12-18.37, p=0.000) definitions. The area under the receiver operating curve was significantly larger for predicting mortality with AKIN classification than with CIN criteria (0.7984 versus 0.7759; p=0.0331). CONCLUSIONS In patients with STEMI treated by pPCI, CI-AKI is a frequent complication irrespective of the criteria used for its definition. AKIN, however, seems to provide a better accuracy in predicting long-term mortality than CIN criteria.

Demonstration of the relationship between heart dimensions and QRS voltage amplitude

This study was undertaken to elucidate the still debated question of the relationship between cardiac volume and QRS voltage amplitude. The authors studied 14 healthy men, aged 24-61 years (mean age, 41.2 +/- 12.1 years). They underwent a reduction in venous return, produced by simultaneously inflating sphygmomanometric cuffs placed around the most proximal portion of each of the four limbs. In basal conditions and 5 minutes after cuff inflation, two-dimensional and M-mode echocardiograms were recorded with vectorcardiographic loops and scalar Frank leads. The reduction of the venous return to the heart induced a significant decrease of the end-diastolic left ventricular diameter (from 52.4 +/- 4.2 to 48.5 +/- 4.6 mm, P < .001), of the R wave amplitude in leads X and Y, of the sum of the R wave amplitudes in the three leads,and of the maximal vector in the frontal and horizontal planes. No significant changes in the heart rate or arterial blood pressure were observed. These results support Brodys theory concerning the relationship between cardiac blood volume and QRS voltage.

Effects of venous return reduction in hypertensive patients: Is there a Doppler diastolic dysfunction index independent of preload reduction?

The aim of this study was to evaluate the effects of preload reduction on the Doppler transmitral flow pattern in the presence of diastolic dysfunction (hypertensive patients) and normal diastolic function (normal subjects) to identify, if present, one or more indexes of abnormal diastolic ventricular filling independent of variations in preload. For this purpose Doppler echocardiography was performed in 17 patients with hypertension and in 18 normal subjects under basal conditions and after 5 minutes of blood pressure cuff inflation at the root of the four limbs. The two groups showed a similar response to preload reduction: a significant reduction in peak velocity and the time-velocity integral of the E wave and in the ratio of peak velocities of E and A waves. Therefore the differences in left ventricular filling patterns between hypertensive and normal subjects observed under basal conditions were still present after preload reduction. The comparison between normal subjects after preload reduction and hypertensive patients in the basal state showed a higher peak velocity and time-velocity integral of the A wave in the latter (61.2 +/- 16.2 vs 46.2 +/- 9 cm/sec [p less than 0.002] and 5.4 +/- 1.8 vs 3.7 +/- 1 cm [p less than 0.002], respectively) with no differences in the ratios of peak velocities and time-velocity integrals of the E and A waves.(ABSTRACT TRUNCATED AT 250 WORDS)

Vectorcardiographic evaluation of diabetic cardiomyopathy and of its contributing factors

SummaryIn order to investigate the prevalence of vectorcardiographic bites, expression of small areas of fibrosis, atrophy or degeneration of the myocardium, we studied, using the vectorcardiograms (VCG) of 101 diabetic patients (35 with insulin-dependent and 66 with non-insulin-dependent diabetes mellitus, aged from 25 to 60 years, without hypertension, coronary artery disease, or intraventricular conduction defects) and 228 normal control subjects, matched for age and sex. The prevalence of bites was 38.6% in diabetic patients and 10.0% in the control group (p<0.001). Diabetic patients were also subdivided into groups according to age, sex, metabolic control, risk factors for coronary heart disease, type of diabetes, duration of diabetes and diabetic microangiopathy. No correlation was found between any of the variables investigated nor of a combination of these, and the presence of bites. We conclude that VCG is a sensitive test for cardiac involvement in diabetic patients but that it cannot be used to identify any specific factor able to influence the onset and evolution of this involvement.

Truncal fat determined by dual-energy X-ray absorptiometry is an independent predictor of coronary artery disease extension

Background Controversy prevails regarding the existence of a correlation between the severity of coronary artery disease (CAD) and the extent and distribution of obesity. Purpose To assess the correlation between total fat, truncal fat (TF), and lean mass, obtained with dual-energy X-ray absorptiometry (DEXA) and standard anthropomorphic indices (body mass index, waist circumference, waist-to-hip ratio) and to verify whether DEXA indices can predict the extent and severity of CAD. Materials and methods Fifty-eight patients (19 females) consecutively referred for coronary angiography underwent physical examination and DEXA assessment of body composition. Results Of the 58 patients enrolled, 22 were overweight and 13 were obese. Significant CAD was found in 39 (67%) patients. DEXA-derived total mass and fat mass enabled us to distinguish overweight from obese patients (P < 0.005), whereas just TF mass correlated with the number of diseased vessels after adjusting for body mass index, sex, age, and smoking habit (odds ratio, 8.68; 95% confidence interval: 1.02-74.10). Conclusion TF determined by DEXA is independently related with CAD extension. Eur J Cardiovasc Prev Rehabil 15:428-433

Real-world clopidogrel utilization in acute coronary syndromes : patients selection and outcomes in a single-center experience

Background: With this study, we sought to identify patient characteristics associated with clopidogrel prescription and its relationship with in-hospital adverse events in an unselected cohort of ACSs patients. Materials and Methods: We studied all consecutive patients admitted at our institution for ACSs from 2012 to 2014. Patients were divided into two groups based on clopidogrel or novel P2Y12 inhibitors (prasugrel or ticagrelor) prescription and the relationship between clopidogrel use and patient clinical characteristics and in-hospital adverse events was evaluated using logistic regression analysis. Results: The population median age was 68 years (57–77 year) and clopidogrel was prescribed in 230 patients (46%). Patients characteristics associated with clopidogrel prescription were older age, female sex, non-ST-elevation ACS diagnosis, the presence of diabetes mellitus and anemia, worse renal and left ventricular functions and a higher Killip class. Patients on clopidogrel demonstrated a significantly higher incidence of in-hospital mortality (4.8%) than prasugrel and ticagrelor-treated patients (0.4%), while a nonstatistically significant trend emerged considering bleeding events. However, on multivariable logistic regression analysis female sex, the presence of anemia and Killip class were the only variables independently associated with in-hospital death. Conclusion: Patients treated with clopidogrel showed a higher in-hospital mortality. However, clinical variables associated with its use identify a population at high risk for adverse events and this seems to play a major role for the higher in-hospital mortality observed in clopidogrel-treated patients.

Intracoronary Epinephrine for Contrast-Medium-Induced Microvascular Obstruction in a Chronically Hemodialyzed Patient

istered intravenously. The fi rst injection of the non-ionic, iso-osmolar CM iodixanol revealed an apparently normal fl ow in the whole left coronary, but at the following angiogram a distal stagnation of previously injected CM was detected ( fi g. 1 ). Coronary Dear Sir, Due to their burden of coronary artery disease, end-stage renal disease (ESRD) patients often need cardiac catheterization procedures. Coronary angiography performed in ESRD patients is associated with a high incidence of complications, mostly radiographic contrast medium (CM)-induced nephropathy [1] . Nevertheless, no data exist about CM-related coronary vasomotor or thrombogenic effects in this population. Epinephrine improves coronary fl ow in patients with no-refl ow after coronary percutaneous intervention [2] , but, to our knowledge, its use in the treatment of coronary fl ow impairment of other etiologies has never been described. Here, we report the use of intracoronary epinephrine in an ESRD patient who experienced a case of sudden impairment in myocardial perfusion during a coronary angiography. A 68-year-old Caucasian male underwent coronary angiography for dilated cardiomyopathy. He presented with hypertension and ESRD treated by hemodialysis. Home therapy consisted of carvedilol 6.25 mg daily, calcitriol 0.25 g daily, calcium carbonate 0.5 g daily, polystyrene sulfonate 30 g daily and erythropoietin 2,000 U every 2 weeks. Blood analysis showed potassium 5.3 mmol/l, sodium 147 mmol/l, creatinine 6 mg/dl, urea 97 mg/dl and hemoglobin 11.5 mg/dl. Basal electrocardiogram revealed a sinus rhythm and a left bundle branch block. Before cardiac catheterization, 1,000 U of heparin were adminReceived: September 29, 2004 Accepted: October 4, 2004 Published online: April 12, 2005