Early abnormalities of left ventricular myocardial characteristics associated with subclinical hyperthyroidism.

The aim of the present study was to analyze heart function in subclinical hyperthyroidism (sHT) in otherwise healthy subjects by new methods using intramyocardial ultrasonic techniques. Twenty-four newly diagnosed and untreated sHT patients (20 women, 4 men; mean age: 42+/-4 yr) and 24 sex- and age-matched healthy volunteers were studied. All subjects were submitted to conventional 2D color-Doppler echocardiography, pulsed wave tissue Doppler imaging (PWTDI) for the analysis of diastolic function, color Doppler myocardial imaging (CDMI) for the analysis of regional strain and strain rate (SR) expression of regional myocardial deformability, and to integrated backscatter (IBS) for the evaluation of intrinsic contractility and tissue characterization. Regional myocardial systolic strain findings were significantly higher in sHT patients when compared with controls (p<0.001). Considering diastolic SR, the early phase of diastolic SR was compromised in sHT subjects as compared with controls (p<0.001). Cyclic variation index (CVI), expression of intrinsic contractility, was significantly higher in sHT subjects in comparison with controls (p<0.0001). IBS values were comparable between the 2 study groups. In conclusion, the present study suggests that in patients with sHT early systolic hyperdeformability and hypercontractility are present, together with impairment of both active and passive phases of diastole. On the contrary, no left ventricular hypertrophy or other structural alterations are documented.

Myocardial systolic strain abnormalities in patients with acromegaly: a prospective color Doppler imaging study.

BACKGROUND: Heart abnormalities are frequent findings in patients with acromegaly: systolic abnormalities are considered to be secondary to diastolic changes. AIM: The aim of the study was to evaluate whether early systolic abnormalities might be revealed in acromegalic patients using the high sensitive color Doppler myocardial imaging (CDMI) technique. PATIENTS AND METHODS: Twenty-two consecutive acromegalic patients with active untreated disease (ACROUNTR) were evaluated at baseline and after a 6-month course with SS analogs (SSa) (ACROSSa); 25 healthy subjects served as controls. All subjects underwent conventional 2D-color Doppler echocardiography, pulse wave tissue Doppler imaging (PW-TDI) and CDMI. RESULTS: Mean left ventricular (LV) ejection fraction did not differ in ACROUNTR and in controls; at variance, ACROUNTR patients had reduced mean LV diastolic function (E/A ratio: 0.96+/-0.3 vs controls: 1.6+/-0.3; p<0.002). Impairment of global LV diastolic function was confirmed by PW-TDI in ACROUNTR patients having a normal systolic function. Regional myocardial systolic strain (epsilon) and strain rate (SR) values, indices of regional systolic heart deformation, were lower in ACROUNTR [epsilonsys (S) -19.8+/-2.9 and epsilonsys (L): -17.7+/-2.2] than in controls [epsilonsys (S): -27.9+/-3.8; p<0.001 and epsilonsys (L): -25.3+/-2.6; p<0.001]. In addition, the early phase of diastolic function, evaluated using SR parameters, was impaired in acromegalic patients (p<0.005 vs controls). Strain and SR values were related to serum GH and IGF-I levels (p<0.02) and greatly improved after a 6-month course with SSa [epsilonsys (S) improved to -23.8+/-3.8 (p<0.05) and epsilonsys (L) improved to -24.7+/-2.4 (p<0.03)]. CONCLUSIONS: Our study confirms that ACROUNTR patients have impaired diastolic function. More important, our study clearly shows that ACROUNTR patients have an impairment of regional myocardial systolic function, which is not secondary to diastolic changes. These intramyocardial functional abnormalities improved during medical treatment of acromegaly. It is conceivable that GH-IGF-I excess has detrimental effects either on the diastolic or the systolic phases of heart function.

Relationship between preclinical abnormalities of global and regional left ventricular function and insulin resistance in severe obesity: a Color Doppler Imaging Study.

BACKGROUND: The aim of this study was to evaluate the relationship between insulin resistance and preclinical abnormalities of the left ventricular structure and function detected in severe obesity by Color Doppler Myocardial Imaging (CDMI). Forty-eight consecutive severely obese patients (Group O) (11 males, 37 females, mean age 32.8+/-7 years) were enrolled. Forty-eight sex- and age-matched non-obese healthy subjects were also recruited as controls (Group C). All subjects underwent conventional 2D-Color Doppler echocardiography and CDMI. The homeostasis model assessment insulin resistance index (HOMA-IR) was used to assess insulin resistance results. Obese subjects had a greater left ventricular mass index (by height) (58.8+/-14 g/m(2.7)) than controls (37+/-8 g/m(2.7)) (P<0.0001), owing to compensation response to volume overload caused by a greater cardiac output (P<0.02). Preload reserve was increased in obese subjects, as demonstrated by a significant increase in left atrial dimension (P<0.0001). Obese patients had a slightly reduced LV diastolic function (transmitral E/A ratio: Group O, 1.1+/-0.8 vs Group C, 1.5 +/-0.5; P<0.002). Cardiac deformation assessed by regional myocardial systolic strain and strain rate (SR) values was significantly lower (abnormal) in obese patients than in controls, both at the septum and lateral wall level. These strain and SR abnormalities were significantly related to body mass index. In addition, the early phase of diastolic function, evaluated using SR, was compromised in obese patients (P<0.001). The HOMA-IR values in obese patients were significantly higher (3.09+/-1.6) than those determined in the control group (0.92+/-0.5) (P<0.0001). The HOMA-IR values, in the obese group, were significantly related to systolic strain and SR values sampled at the septum level (P<0.0001). CONCLUSION: In conclusion, this study has demonstrated that obese patients pointed out systolic structural and functional abnormalities at a preclinical stage, in particular through strain and SR analysis; on the other hand, those altered CDMI parameters well distinguish obese subjects as compared with the control group. Furthermore, another main finding of the study was that myocardial deformation (systolic strain) could have a correlation with insulin resistance level.

Coronary microcirculation into different models of left ventricular hypertrophy-hypertensive and athlete's heart: a contrast echocardiographic study.

The study was carried out in two different models of left ventricular hypertrophy: athlete's heart and essential arterial hypertension. Three groups of strictly age-matched males were studied: one group of 10 young adult untreated essential hypertensive patients (H), a second group of 10 athletes (A), and a group of 10 healthy individuals as controls (C). A Sonos 5500 echograph with S4 harmonic transducer was used with Levovist (ultrasonic tracer) before and after dipyridamole injection; digitised images of quantitative myocardial contrast echocardiography were collected with Power Harmonic Doppler. Angio images were analysed using dedicated PC software by placing a region-of-interest on the septum. Peak intensity, half-time (HT), the area under the curve of appearance and disappearance of microbubbles at 2/3 of PI, both in absolute and indexed values (/LVMi), were sampled. The per cent increase of PI after dipyridamole was significantly higher in C (+73%, P < 0.01) than in H (+31%) and in A (+33%) (P < 0.05). The area of appearance was significantly lower in H in comparison with C and A, both at rest and after vasodilatation. The disappearance area after dipyridamole was significantly higher in C and in A (+124%) than in H (+104%) (P < 0.05). Some hypothesis could be made: an impairment in the coronary microcirculatory function in hypertensive patients could be because of an in-crease in the arteriolar resistance. Angiogenesis and several different functional adaptations are the mechanisms that allow an optimal distribution of oxygen and of substrates to the hypertrophied myocardium of the athletes.

Effects of abciximab on microvascular integrity and left ventricular functional recovery in patients with acute infarction treated by primary coronary angioplasty.

AIM: To investigate the effect of abciximab on microvascular integrity and left ventricular (LV) functional recovery in patients with acute myocardial infarction (MI) treated by primary coronary angioplasty (PTCA). METHODS AND RESULTS: Thirty-one patients (27 males; age 39-76 years) with first, acute MI (<6 h after onset) were randomized to receive either abciximab+primary PTCA (n=17) or primary PTCA alone (n=14). Baseline characteristics of the two groups were similar. Myocardial reperfusion was studied shortly after PTCA by corrected TIMI frame count (cTFC) and intracoronary myocardial contrast echocardiography (MCE), after 48 h by intravenous MCE using intermittent, harmonic power Doppler, and after 1 month by intravenous MCE and 99 mTc-tetrofosmin SPECT. The patients treated with abciximab showed a shorter cTFC (23+/-4 vs 30+/-9 frames; P<0.05), a more preserved microvascular integrity shortly after PTCA (77% vs 55%; P<0.01), after 48 h (86% vs 50%; P<0.005) and at 1-month follow-up (86% vs 54% by MCE, P<0.001, and 68% vs 60% by SPECT, P<0.005) than patients treated with PTCA alone. Abciximab patients also showed a better recovery of LV function, as demonstrated by greater reduction in wall motion score index (1.4+/-0.3 vs 1.5+/-0.2; P<0.05) and increase in LV ejection fraction (53+/-7% vs 48+/-5%; P<0.001). CONCLUSIONS: Abciximab improves microvascular perfusion and LV functional recovery in primary PTCA.

Coronary microcirculation in essential hypertension: a quantitative myocardial contrast echocardiographic approach.

AIMS: The aims of the present study were: (a) to demonstrate whether quantitative myocardial contrast echocardiography can detect the increase in coronary flow induced by dipyridamole infusion vasodilation through the myocardial opacification due to the transit of microbubbles, both at rest and after dipyridamole induced vasodilation; (b) to explore the coronary microcirculatory function before and after dipyridamole in two different models: asymptomatic and relatively young hypertensive patients with a mild degree of left ventricular hypertrophy, and healthy controls. METHODS AND RESULTS: Two groups of strictly age-matched males were studied (case-control study): 10, relatively young and asymptomatic essential hypertensive patients with a mild degree of left ventricular hypertrophy with a normal left ventricular function, and 10 healthy controls. The main findings were: the microbubbles' appearance area was significantly lower in hypertensive patients than in controls (P<0.05) because of a significantly lower time to peak. The peak intensity at rest was higher in hypertensives than in controls (P<0.05); but the per cent increase after vasodilatory stimulus was significantly higher in controls (+71% in controls vs +31% in hypertensives; P<0.05). The microbubbles' disappearance area was comparable in both groups at rest; the per cent increase of this parameter after dipyridamole was significantly higher in controls (+124%) than in hypertensives (+90%) (P<0.05). The results achieved in this study documented that the coronary microcirculation in hypertensive patients presenting a mild degree of left ventricular hypertrophy, explored with quantitative myocardial contrast echocardiography, showed a different behaviour in comparison with controls, in the vasodilatory response to dipyridamole. CONCLUSION: The coronary microcirculation in hypertensives showed a reduced vasodilation capacity of the resistance arterioles under dipyridamole induced vasodilatation, and a possible impairment of the endothelium dependent vasodilation. This happened despite an increase in the left ventricular mass, where the relation between capillary bed distribution and hypertrophied myocardium (rarefaction phenomenon) is not completely respected.

Relation between dobutamine trans-thoracic echocardiography, 99Tcm-MIBI and 18FDG uptake in chronic coronary artery disease.

The relationships between rest conditions of myocardial asynergy, response to dobutamine administration, perfusion and glucose metabolism were examined in 12 patients with chronic coronary artery disease and left ventricular dysfunction. We evaluated (1) rest and stress myocardial perfusion by 99Tcm-methoxyisobutylisonitrile (MIBI) and single photon emission tomography (SPET), (2) rest myocardial segmental wall motion by trans-thoracic echocardiography and low-dose dobutamine, and (3) myocardial metabolism by [18F]-2-fluoro-2-deoxy-D-glucose (18-FDG) and positron emission tomography (PET), in the fasting state. The analysis was carried out on 16 left ventricular myocardial segments. The SPET studies were analysed semi-quantitatively by normalization to the peak activity. Wall motion was assessed by a visual score. An 18FDG index was determined as the tissue/blood pool radioactivity ratio in each segment. The results showed: (1) remarkably good agreement between the number of dobutamine responsive segments and 18FDG positive segments among those that were only moderately hypoperfused and hypokinetic; (2) a smaller number of dobutamine responsive segments than 18FDG positive segments among those that were hypoperfused and akinetic; and (3) the presence of 18FDG in 50% of the segments that were severely hypoperfused and akinetic or dyskinetic and without improvement with dobutamine. These results indicate that in severely hypoperfused and akinetic or dyskinetic segments, trans-thoracic echocardiography under inotropic stimulation provides little additional information compared with that obtained with rest echocardiography and perfusion studies; the assessment of 18FDG uptake provides information that is complementary to that obtained by perfusion assessment, rest and dobutamine trans-thoracic echocardiography.

Identification of hibernating myocardium: a comparison between dobutamine echocardiography and study of perfusion and metabolism in patients with severe left ventricular dysfunction.

The distinction between fibrotic and viable myocardium is a key issue in patients with coronary artery disease and left ventricular dysfunction. Metabolic imaging with positron emission tomography (PET) and labeled tracers, along with the study of myocardial perfusion, is now available to identify hibernating myocardium. However, PET imaging of myocardial metabolism is a high-cost and time-consuming technique, and requires an on-site cyclotron. The aim of this study is to test the reliability of dobutamine echocardiography (DE) compared with PET imaging, for the identification of hibernating myocardium. In 16 patients, scheduled for myocardial revascularization, left ventricular shapes were divided in eight segments both for echocardiographic and nuclear study evaluation. All patients underwent a technetium 99m MIBI single-photon emission tomography stress-rest study of perfusion, a fluorine-18-labeled deoxyglucose (FDG(/PET study of metabolism, and a DE test (baseline, at a 5 micrograms/kg/min infusion of dobutamine for 8 minutes and at a 10 micrograms/kg/min dose for additional 8 minutes). Neither myocardial ischemia nor arrhythmia occurred during the DE test. Baseline echocardiograms showed 90 segments with wall motion abnormalities: wall motion impairment was decreased or reversed in 33 of 90 segments; it remained unchanged in 57 of 90 segments. In 32 of 33 segments considered viable on the basis of DE and in 21 of 57 segments with unchanged kinesis, some degree of FDG was detected. Thus, sensitivity and specificity of DE compared with nuclear studies was 60% and 97% respectively. Moreover, a good correlation and agreement (kappa = 0.51) between DE and the presence of FDG were found. We conclude that DE is a safe and reliable test for the screening of hibernating myocardium in patients with chronic coronary artery disease and left ventricular dysfunction.

[An echographic study of left ventricular function in acute myocardial infarct undergoing thrombolysis]. / Studio ecocardiografico della funzione ventricolare sinistra nell'infarto miocardico acuto sottoposto a trombolisi.

To evaluate the changes of left ventricular diastolic and systolic function and the timing of these changes in the early stages of acute myocardial infarction, serial echocardiograms were performed in 10 male patients (mean age of 56 years) with acute myocardial infarction, undergoing reperfusion by thrombolysis (recombinant tissue plasminogen activator). Echocardiograms were performed before reperfusion and 3, 6, 12, 24, 48, 72 hours, 7 and 14 days after thrombolysis. Significant differences of heart rate, systolic and diastolic blood pressure, left ventricular end diastolic volume, end-systolic volume and ejection fraction were not found. The mean regional wall motion index improved from 1.02 +/- 0.50 to 0.89 +/- 0.51 (p less than 0.05) at 48 hours; to 0.79 +/- 0.46 (p less than 0.01) at 72 hours; to 0.69 +/- 0.43 (p less than 0.001) at 7 days and to 0.61 +/- 0.40 at 14 days (p less than 0.001). The deceleration time decreased from 223 +/- 33 to 169 +/- 30 ms (p less than 0.001) 24 hours after reperfusion without further improvement. E peak velocity and E/A ratio significantly increased at 72 hours, while A peak velocity was not statistically different. A slow and progressive recovery of left ventricular function occurred after thrombolysis in acute myocardial infarction. Left ventricular diastole improves earlier while regional systolic function improves slowly till the hospital discharge.

[Coronary disease in patients operated on for valvulopathy]. / Coronaropatia negli operati per valvulopatia.

In order to evaluate the influence of a significant coronary artery disease in patients with valvular heart disease or with prosthetic valves, we reviewed literature and our own experience. The incidence of coronary artery disease in valvulopathies has been diffusely studied and reported and, in a consecutive series of our hemodynamic studies, resulted 11%. The influence of a coronary artery disease on early and late results of a surgical procedure is different whether the coronary artery disease is operated or not. In particular, the combined surgery shows a higher early mortality, but a much better long-term prognosis. In addition, sometimes surgery introduces rare causes of coronary artery disease. Finally, it seems that coronary artery disease arises very rarely in patients undergone valvular surgery or, at least, patients rarely complain anginal symptoms in the post-surgical follow-up. In our experience on 529 patients only 6 complained typical angina and only 2 showed a coronary artery disease not present at the time of operation.

[The evaluation of the cardiotoxicity of 4'-epidoxorubicin at high doses]. / Valutazione della cardiotossicità della 4'-epidoxorubicina ad alte dosi.

Twenty-eight patients with small cell lung cancer were treated with high dose 4'-epidoxorubicin (EDX). Fifteen patients underwent EDX monotherapy (cumulative dose: 800 mg/m2) while 13 were treated with EDX (cumulative dose: 660 mg/m2) associated with cyclophosphamide, etoposide and cisplatin. A 2D-echo was performed in basal condition, after the third and sixth dose and 2 months after the end of the therapy. In the patients without cardiovascular disease (n = 19) left ventricular end-diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) were unchanged. The patients with coronary artery disease (n = 5) showed a statistically significant decrease in EF with an increase of ESV. All patients with systemic hypertension (n = 4) showed a significant reduction of EF and a significant increase of ESV and EDV.