[Stress imaging in coronary artery disease: state of the art]. / Stress imaging nella cardiopatia ischemica: stato dell'arte.

To date, several diagnostic tools allow an accurate non-invasive evaluation of coronary artery disease; this is due to the great progress in echocardiographic and nuclear imaging techniques in the last 10 years. The large availability of different stress imaging techniques allows to choose the most appropriate technique for each patient according to the clinical characteristics. This paper presents the state of the art of echocardiographic and nuclear stress imaging for the diagnosis of coronary artery disease and for the prognostic stratification of infarcted patients. Advantages and limits of the different techniques are described rather than putting in competition echo and nuclear cardiology as has often been done in the past. Cardiologists should select among the various techniques on the basis of clinical characteristics of single patients, center's experience and an objective evaluation of economical aspects.

Gender differences in the risk of ischemic stroke associated with aortic atheromas.

BACKGROUND AND PURPOSE: Atherosclerotic plaque of the proximal portion of the aorta is associated with an increased risk of ischemic stroke in the elderly. Different cutoffs of plaque thickness have been used in the literature for risk stratification and have been applied to both men and women. However, the assumption that the relationship between plaque thickness and stroke risk is the same in the 2 genders has not been proven. The aim of this study was to evaluate whether the prevalence of different degrees of aortic plaque thickness differed in men and women with ischemic stroke. METHODS: We performed transesophageal echocardiography in 152 patients aged >59 years with acute ischemic stroke (76 men and 76 women) and in 152 control subjects of similar age (70 men and 82 women). Odds ratios (ORs) for ischemic stroke with 95% CIs for different plaque thickness definitions were calculated for the overall group and separately for men and women by logistic regression analysis after adjusting for age, arterial hypertension, and hypercholesterolemia. RESULTS: Aortic plaques >/=4 mm were significantly more frequent in men than in women (31.5% versus 20.3%, respectively; P:=0.025) and were associated with ischemic stroke in both men (adjusted OR 6.0, CI 2.1 to 16.8) and women (adjusted OR 3. 2, CI 1.2 to 8.8). However, plaques 3 to 3.9 mm in thickness had a significant association with stroke in women (adjusted OR 4.8, CI 1. 7 to 15.0) but not in men (adjusted OR 0.8, CI 0.2 to 3.0). Plaques <3 mm were not associated with a significantly increased stroke risk for either sex. CONCLUSIONS: Smaller aortic plaques are significantly associated with ischemic stroke in women but not in men. If the increased prevalence of smaller plaques in women is confirmed to be associated with increased risk for embolic stroke, different cutoff points may have to be adopted in men and women for risk stratification and for decisions regarding medical intervention.

Aortic atheroma morphology and the risk of ischemic stroke in a multiethnic population.

BACKGROUND: Protruding atheromas in the aortic arch are an independent risk factor for ischemic stroke in the elderly. However, the role of atheroma morphologic characteristics (ulceration and mobility) has been less well characterized. Moreover, data have been obtained in predominantly white populations, and little is known about the association between atheromas and stroke in minorities. METHODS AND RESULTS: We performed transesophageal echocardiography in 152 elderly patients with stroke (58 white, 45 black, 49 Hispanic) and in 152 age- and race/ethnicity-matched control patients. Atheromas were classified as small (<4 mm in thickness), large noncomplex (> or =4 mm, no ulceration or mobility), and complex (ulcerated or mobile). Logistic regression analysis was performed to assess the risk of stroke associated with different definitions of atheroma in the overall group and in the race-ethnic strata after adjusting for the presence of other stroke risk factors. Complex atheromas were strongly associated with stroke in the overall group (22.4% in cases, 2.6% in control patients; adjusted odds ratio [OR] 17.1, 95% confidence intervals [CI] 5.1 to 57.3), whereas large noncomplex atheromas conferred a mildly increased stroke risk (22.4% vs 16.5%; adjusted OR 2.4, 95% CI 1.1 to 5.1). Complex atheromas also were strongly associated with stroke in whites (adjusted OR 24. 3, 95% CI 3.9 to 150.6) and Hispanics (adjusted OR 13.9, 95% CI 1.4 to 136). In blacks, complex atheromas were significantly more frequent in cases (15.6% vs 0%; P =.006), but their absence in control patients precluded the calculation of the OR. Complex atheromas were twice as frequent in white patients with stroke (32. 3%) than in black or Hispanic patients (15.6% and 16.3%, respectively; P =.05). CONCLUSIONS: Aortic atheroma complexity rather than size is strongly associated with ischemic stroke in the elderly. Complex atheromas are significantly associated with stroke in all 3 race-ethnic subgroups.

Spontaneous resolution of pulmonary venous thrombosis after lung transplantation.

Thrombus formation at the pulmonary venous anastomotic site after lung transplantation may have catastrophic consequences, including allograft failure and stroke. However, treatment with systemic anticoagulation may facilitate bleeding in the early postoperative period. In the present report, we describe the clinical and transesophageal echocardiographic findings of pulmonary venous thrombosis in two patients in the immediate postoperative period after lung transplantation. Treatment with systemic anticoagulation was not feasible because of extensive postoperative thoracic bleeding in each instance. A conservative approach was taken on the basis of the small size of each thrombus and lack of accelerated flow velocity at the site of the thrombus. Each thrombus resolved spontaneously without clinical sequelae. These two cases suggest that thrombus size and flow velocity at the anastomotic site may be used to guide the clinical management of pulmonary venous thrombosis after lung transplantation.

Transesophageal echocardiography-guided transvenous biopsy of a cardiac sarcoma.

Transvenous endomyocardial biopsy is a well established procedure to diagnose rejection after heart transplantation as well as to assess for other cardiomyopathic processes. However, it is rarely used to obtain samples of unidentified cardiac masses. We report a case of a primary cardiac sarcoma in which the histologic diagnosis was provided by transesophageal echocardiography-guided transvenous biopsy. This procedure is accurate and can avoid the potential risk of a diagnostic thoracotomy.

Improved atrial function in bicaval versus standard orthotopic techniques in cardiac transplantation.

Atrial geometry is preserved in the bicaval technique of cardiac transplantation. Using Doppler echocardiography, we investigated the impact of this technique on preservation of atrial function and found that echocardiographic indexes of atrial function are improved in bicaval cardiac transplants versus the standard orthotopic transplants.

Effects of exposure to high altitude on plasma endothelin-1 levels in normal subjects.

OBJECTIVE: To assess whether the hypoxia associated with exposure to high altitude affects plasma endothelin-1 levels, and whether changes in endothelin-1 are related to those in systemic and pulmonary blood pressure. DESIGN: Eight normal subjects ascended Mount Everest to an altitude of 5050 m within a period of 8 days (study 1) and 10 ascended Mount Rosa in the Italian Alps to an altitude of 4559 m within 2 days (study 2). In study 1 systemic blood pressure, heart rate, haematocrit, haemoglobin oxygen saturation (evaluated by percutaneous oximetry) and venous plasma endothelin-1 were measured several times during the ascent, and twice more during the time spent at high altitude. In study 2 the same parameters as well as systolic pulmonary pressure by echocardiography were evaluated on the second day of resting at 4559 m. In both studies, data obtained during the expeditions were compared with those collected from the same subjects at sea level. RESULTS: In study 1 plasma endothelin-1 increased progressively up to 4240 m (from 1.8 +/- 0.1 pg/ml at sea level to 2.7 +/- 0.2 pg/ml) and decreased slightly thereafter; these increments were directly related to the decrements in percutaneous oxygen saturation, which, at that altitude, fell from 98.6 +/- 0.2% at sea level to 80.8 +/- 0.4%. Blood pressure and haematocrit also rose in response to exposure to high altitude but these changes were not related to changes in endothelin-1. In study 2 the increments in plasma endothelin-1 were similar to those observed in study 1 and the changes again correlated with changes in oxygen saturation as well as with those in systolic pulmonary pressure. On average, systolic pulmonary pressure increased from 19 +/- 1 to 26 +/- 1.9 mmHg, whereas systemic blood pressure and haematocrit were unchanged. CONCLUSION: Exposure to high altitude is associated with consistent increases in plasma endothelin-1. This is probably the result of augmented secretion of the peptide in response to hypoxia and may contribute to the physiological adaptation of the pulmonary circulation to this condition.

Endothelin-releasing stimuli and calcium antagonists in normal and pathological conditions.

BACKGROUND: Endothelin-1 is a potent vasoconstrictive peptide which circulates in blood at very low concentrations. It is mostly released from endothelial cells towards the vascular smooth muscle cells. Therefore studies addressed at increasing endothelin-1 production using physical stimuli may easily fail to cause sizeable modifications in plasma endothelin levels. Upright posture and exposure to cold, the two maneuvers so far most commonly used in humans, often have inconsistent effects on plasma endothelin-1. RECENT FINDINGS: In recent studies we have found that exposure to high altitude (4500-5000 m) caused, in normal subjects, significant increases in endothelin-1 which were correlated with those of mean arterial pressure and of systolic pulmonary pressure. CONCLUSIONS: Hypobaric hypoxia appears to stimulate the secretion of endothelin-1 and this response may contribute to the adaptation by the systemic and pulmonary circulation to the stress of altitude. If this can be confirmed, calcium antagonists, which are known to antagonize endothelin-1 mediated vasoconstriction, may be used to alleviate the pulmonary hypertension that occasionally occurs under these specific circumstances.

[Echography in aneurysm of the interatrial septum]. / L'ecocardiografia nell'aneurisma del setto interatriale.

Atrial septal aneurysm can be detected by subcostal echocardiography as a bulge of the intermediate interatrial septum, ballooning toward the right atrium. We retrospectively revised 5412 echo examinations, consecutively performed in our laboratory, and we found 14 cases of atrial septal aneurysm (0.26%), mean age 36 +/- 15 years, 9 males and 5 females. In 7 patients atrial septal aneurysm was wide, including the whole atrial septum; in 5, only cranial two-thirds of the septum were involved and in 2, it regarded only the intermediate septum. No patients referred to arrhythmias, syncope, embolism, endocarditis or transient ischemic neurologic disorders. Cardiac abnormalities or defects were associated to atrial septal aneurysm in 12/14 patients: they consisted of atrial septal defect, mitral valve prolapse, false ventricular tendons or persistent Chiari network. Atrial left-to-right shunt was detected in all 6 cases with atrial communication. Considering each single associated cardiac abnormality, the prevalence of atrial septal aneurysm was 7% in patients with atrial septal defect, 1.7% in those with mitral valve prolapse, 6.6% in persistent Chiari network and 0.9% in false ventricular tendons. In conclusion, echocardiography is the first-choice technique to detect atrial septal aneurysm and other related cardiac defects.

Echocardiographic evaluation of right heart responses to sublingual nifedipine in dilated cardiomyopathy.

Twelve patients with dilated cardiomyopathy were studied in order to evaluate whether the favourable effect of Nifedipine on the right heart is due to a direct action of the drug on pulmonary resistances or is related to an improvement of left ventricular function. Echocardiographic examination of left and right heart was performed at basic conditions, after Nifedipine treatment--20 mg sublingually--and after 20 minutes of oxygen breathing (FiO2 75%). This was done in order to verify if oxygen vasodilating action could potentiate the Nifedipine effect. Echocardiographic date were obtained in basic conditions, 10, 20 and 30 minutes after Nifedipine and immediately after oxygen breathing. Ten normal subjects were used for comparison for basic data. Peak Nifedipine activity was observed 10 minutes after administration. At this time inferior vena cava emptying index and systolic pulsation were significantly increased, whereas left and right ventricle isometric contraction time, left and right ventricle ejection time, left and right ventricle isovolumetric relaxation time, end-diastolic left ventricular diameter, inferior vena cava diameters and systolic blood pressure had decreased, thus showing the favourable effect of Nifedipine of both heart sides. Heart rate did not significantly change. Oxygen inhalation induced a significant decrease of right ventricular isovolumetric relaxation and an increase of the inferior vena cava indexes, suggesting an improvement in right heart function, without any change in other parameters. No significant difference was found between data after-oxygen and data obtained 10' after Nifedipine, showing that the Nifedipine effect was not potentiated by oxygen.(ABSTRACT TRUNCATED AT 250 WORDS)

[Echocardiographic aspects of false intraventricular tendons]. / Aspetti ecocardiografici dei falsi tendini intraventricolari.

A series of 4260 consecutive echocardiographic examinations, performed in 5 Cardiological Centers was examined, identifying 125 intraventricular false tendons (FTs) in 100 cases (55 normals and 45 with heart disease) of whom 31 were female and 69 male, aged 3 to 82 years. An anatomo-morphological study was possible in 9 cases, dead for stroke or heart failure, on autopsy, and in 7, on heart surgery. A phonocardiogram was performed in all normals and in 20 patients. On echocardiography, FTs appeared as an echo-producing string-like structure, straight between the septum and the ventricular free wall, mobile during the cardiac cycle, without systolic thickening and any relation with the atrioventricular valvular apparatus. The prevalence of FTs was 2.3%; it was 3.2% to 5.3% in younger people. FTs were located in the right ventricle (4 cases), left ventricle (95 cases) or in both (1 case). Their site was left apical (45 FTs), right apical (2 FTs), right (3 FTs) and left (20 FTs), upper septum-to-free wall (55 cases). In 1 case hypertrophy of trabeculae of the left ventricle was detected. FTs were single (79 cases), double (19 cases), multiple (2 cases), short (42 cases), long (58 cases), thick (45 cases) and thin (55 cases). They showed a membrane-like motion (thick FTs-45 cases) and a valve-like motion (thin FTs-55 cases). Innocent murmur was detected in 50 of 55 normals and related to thin FTs. Of 16 cases examined anatomically and histologically, FTs were fibrous in their distal portion and fibro-muscular in the proximal one in 12 cases, whereas they were entirely fibrous-muscular in 4 cases. The site and location of FTs detected by echo were confirmed by anatomy in all cases. In 4 cases other 9 FTs, not detected on echocardiography, were found. These data suggest that echocardiography is a useful tool to detect intraventricular FTs and differentiate them from other echo-producing structures. Although a relationship between FTs and heart disease has not been found, their presence could be responsible of innocent murmur in many normal subjects.

Echocardiographic assessment of the inferior vena cava wall motion for studies of right heart dynamics and function.

Using subcostal echocardiography, 97 patients with diseases involving the right side of the heart and 15 normal subjects were examined in order to study the inferior vena cava (IVC) wall motion. All cases had a diagnostic cardiac catheterization and routine echocardiogram. The jugular pulse (JP) was recorded in 35 random cases contemporary to the IVC and tricuspid valve (TV) tracings. The aim of the study was to evaluate the variations of the IVC diameters in different cardiopathies and in relation to the right atrial mean pressure and the time-relationship of the IVC wall motion related to the cardiac rhythm and cycle, respiratory events, and JP and TV waves. The a, b, v, and y waves were identified on the IVC tracings and related to the respective waves of the JP and the points of closure and opening of the TV. The IVC a and v waves were coincident with the TV closure and opening, and therefore, considered as moments of maximal presystolic and systolic filling of the IVC. The JP a wave inscribed before, whereas the v wave did so after the same IVC waves, respectively. The IVC a wave was due to the atrial contraction and influenced by the cardiac rhythm. The emptying index (EI) was calculated from the diameters in a and b as a - b/a X %, whereas the collapsability index (CI) was calculated from the expiratory and inspiratory diameters as Ex - In/Ex X %, obtaining a good correlation with the right atrial mean pressure. Finally, the percentage systolic pulsation (SP) was calculated from the diameters in b and v as b - v/b X %. The indices of function of the IVC have been very useful in the evaluation of patients with raised heart pressure, tricuspid regurgitation, and pericardial effusion. From the present investigation it results that the IVC wall motion, more so than the JP waves, is an expression of right atrial and ventricular events, and that the above indices are an expression of the atrial and ventricular function in relation to the hemodynamic situation.

Detection of atrial septal defect with left-to-right shunt by inferior vena cava contrast echocardiography.

Contrast echocardiography was used before cardiac catheterisation in 37 patients with atrial septal defect and a left-to-right shunt and in 18 patients with a raised right atrial and ventricular pressure to assess the contrast echo effect in the inferior vena cava. Using two dimensional contrast apical echocardiography we found a negative contrast echo effect within the right atrium in many but not all patients with atrial defect. Contrast echoes entering the inferior vena cava during presystole or early to mid-diastole were detected in patients with heart disease causing raised right atrial and ventricular pressures and also in all patients with atrial septal defect. No contrast echo effect in the inferior vena cava was detected in 10 normal subjects. The sensitivity of this contrast pattern in the inferior vena cava in diagnosing atrial septal defect was 100%. When other conditions causing raised right atrial pressure were excluded, the specificity and predictive accuracy were 100% for both. The presystolic contrast echo effect in the inferior vena cava, semiquantitatively graded, correlated with the size of the shunt determined by oximetry. In 20 patients re-examined after the surgical correction of the atrial septal defect, no presystolic contrast echo effect was detected in the inferior vena cava. Contrast echocardiography of the inferior vena cava is a valuable and reliable method for diagnosing atrial septal defect with left-to-right shunt.

Echocardiographic assessment of left ventricular wall motion in hypertrophic cardiomyopathy.

M-mode and two-dimensional parasternal long axis view echocardiography, and left anterior oblique cineangiography were employed to assess the left ventricular wall motion in 10 normal subjects (N) and in 25 patients with hypertrophic cardiomyopathy: 7 patients with symmetric hypertrophy (SH) and 6 patients with apical cardiomyopathy (AHCM) and no intraventricular gradient; 12 patients with hypertrophic obstructive cardiomyopathy and asymmetric septal hypertrophy with resting intraventricular gradient (6 pts) (HOCM-R) or gradient occurring only after isoproterenol infusion (6 pts) (HOCM-I). The left ventricle was divided into five portions: upper and lower septum, upper and lower posterior wall and apex. The excursion and thickness of the upper and lower portions of the septum and posterior wall were measured in all patients and compared to 10 normal subjects (N). From the superimposed end-diastolic and end-systolic echo frames and angio silhouettes a chordal and a radial-chordal method were used, respectively, to measure the motion of the left ventricular wall segments. In SH the left ventricular wall motion was qualitatively similar to N but a little reduced; the thickness was increased and no pressure gradient was present. In AHCM the lower septum, posterior wall, and apex showed significantly increased thickness and motion compared to N and compared to the upper portions of the septum and posterior wall. No gradient was present. In HOCM-R the upper septum moved towards the apex, the lower septum, upper posterior wall and lower posterior wall moved towards the left ventricular cavity. The upper posterior wall was hyperkinetic compared to N and compared to the lower posterior wall, resting gradient and SAM was present in all. In HOCM-I the upper septum moved towards the apex; the posterior wall was hyperkinetic (the excursion was a little wider in the lower posterior wall than in the upper posterior wall). No gradient was recorded at rest, but it could be provoked by isoproterenol. Echocardiography provides precise information on left ventricular wall motion in hypertrophic cardiomyopathy. Hyperkinesis of the lower left ventricular wall is related to AHCM; hyperkinesis of the upper posterior wall and the motion of the upper septum towards the apex are related to HOCM-R. Hyperkinesis of the lower posterior wall is related to HOCM-I. SAM and pressure gradients may be related to the hyperkinesis of the upper posterior wall. Finally, the septum is not an immobile structure in HOCM, since it moves mainly from the base to the apex and a less (or not at all) towards the posterior wall.

Reliability of subcostal TD echocardiography to detect atrial septal defect.

Echocardiography was used in 40 patients with atrial septal defect (ASD), diagnosed by cardiac catheterization. A dilated right ventricle and abnormal interventricular septal motion were observed at M-mode echocardiography in patients with large L-R shunt. The two-dimensional apical four chamber view was reliable to detect the ostium primum type but not the secundum type of ASD. Moreover the presence of false positives reduced the specificity and predictivity of this approach. The two-dimensional subcostal view provided a direct visualization of the interatrial communication (sensitivity, specificity and predictivity = 100%) and whether the defect was in the uppermost, lowermost or midportion of the septum. Subcostal two-dimensional echocardiography is considered valuable and reliable technique to detect atrial septal defect and the type of the defect itself.

Contrast echocardiographic features of pulmonary hypertension and regurgitation.

Linear contrast echo configuration on the pulmonary valve M-mode echogram was assessed in 28 patients with pulmonary hypertension, in 10 with pulmonary regurgitation, and in 10 normal subjects. Contrast echo parallel lines filling the total systolic phase of the pulmonary valve were recorded in normal subjects. Contrast echo lines stopping in early systole around the pulmonary valve mid-systolic notch were seen in all the patients with pulmonary hypertension in relation to changes with the pulmonary flow. Contrast echo lines reversing the early diastole and crossing the pulmonary valve echogram during diastole were detected in all the patients with pulmonary regurgitation, consistent with the reversed flow across the valve. The use of contrast echocardiography to diagnose both pulmonary hypertension and regurgitation may provide further useful information, particularly when the orientation and time of appearance of the contrast echo lines are related to the systolic and/or diastolic phases of the pulmonary valve M-mode echogram.

Contrast echocardiography of the inferior vena cava.

M-mode and two-dimensional subcostal contrast echocardiography were used in 67 patients and 10 normal subjects to evaluate the contrast echo effect on the inferior vena cava echogram in relation to the cardiac cycle and respiratory events. No contrast echoes were recorded in the inferior vena cava in normals during normal breathing. Contrast echoes were recorded entering the inferior vena cava in systole in 20 patients with tricuspid regurgitation and in pre-systole in patients with atrial septal defect and left-to-right shunt and in some of the patients with elevated right atrial and ventricular end-diastolic pressure. Forced inspiration increased the contrast echo effect and determined the penetration of microbubbles into the inferior vena cava. This latter feature occurred in all the patients and only in 1 normal subject. The entry of the contrast echoes into the inferior vena cava was attributed to the high right atrial ventricular end-diastolic pressure and to the reversed flow, from the right ventricle to the right atrium and inferior vena cava in tricuspid regurgitation and from the left atrium to the inferior vena cava in atrial septal defect. The contrast echocardiographic diagnosis of tricuspid regurgitation appeared to be most reliable. New encouraging results were obtained by this technique in diagnosing atrial septal defect and left-to-right shunt. The first appearance of the contrast, the time of appearance in relation to the cardiac cycle and the direction of the to and fro motion of contrast echoes were the most important factors considered for a correct diagnosis.