Excimer laser technology in percutaneous coronary interventions: Cardiovascular laser society's position paper.

Excimer Laser Coronary Atherectomy (ELCA) is a well-established therapy that emerged for the treatment of peripheral vascular atherosclerosis in the late 1980s, at a time when catheters and materials were rudimentary and associated with the most serious complications. Refinements in catheter technology and the introduction of improved laser techniques have led to their effective use for the treatment of a wide spectrum of complex coronary lesions, such as thrombotic lesions, severe calcific lesions, non-crossable or non-expandable lesions, chronic occlusions, and stent under-expansion. The gradual introduction of high-energy strategies combined with the contrast infusion technique has enabled us to treat an increasing number of complex cases with a low rate of periprocedural complications. Currently, the use of the ELCA has also been demonstrated to be effective in acute coronary syndrome (ACS), especially in the context of large thrombotic lesions.

Catheter ablation of atrial incisional tachycardia mistaken for atrial flutter.

Incisional sustained tachycardias are frequent in patients who have undergone a surgical repair of interatrial defect. A 43-year-old woman with drug refractory, highly symptomatic, persistent atrial tachycardia in the last year, was referred to our unit for catheter ablation. The patient had undergone a cardiac operation for repairing interatrial secundum ostium type defect with a patch five years before. A previous radiofrequency ablation procedure had been performed for common atrial flutter. We describe a case of incisional atrial tachycardia ablation guided by the new EnSite NavX system equipped with a new electroanatomic mapping system.

Work capacity and oxygen uptake abnormalities in hyperthyroidism.

AIM: The aim of our study was to evaluate the haemodynamic and the respiratory response to exercise in patients with hyperthyroidism before and 30 days after normalized thyroid hormones levels. These findings were compared with those of 10 control patients. METHODS: Thirty patients (23 women, aged 34.3 +/- 12 years) with untreated hyperthyroidism were studied. Twenty-four patients were treated with methimazole, 13 of which were also treated with propranolol. Six patients underwent surgery. A symptom-limited cardiopulmonary exercise test and an echocardiography were performed in all patients. RESULTS: At rest patients with hyperthyroidism showed at echocardiography an increased cardiac index (P = 0.006 vs euthyroid, P = 0.007 vs normal) and a higher ejection fraction (P = 0.008 vs euthyroid, P = 0.007 vs normal). The duration of the exercise was lower in hyperthyroid patients (P = 0.006 vs euthyroid; P = 0.0068 vs normal). Anaerobic threshold was reached at 49.6% of peak VO2 during hyperthyroidism, at 60.8% during euthyroidism (P = 0.01) and at 62% in normal (P = 0.01). Work rate was lower in patients with hyperthyroidism at anaerobic threshold (P = 0.01 vs euthyroid, P = 0.03 vs normal) and at maximal work (P = 0.001 vs euthyroid, P = 0.01 vs normal). Patients in hyperthyroidism showed a lower increment of heart rate between rest and anaerobic threshold (P = 0.021 vs euthyroid, P < 0.0001 vs normal) and a lower VO2 at anaerobic threshold (P = 0.03 vs euthyroid; P = 0.04 vs normal). Oxygen pulse at anaerobic threshold was significantly reduced in hyperthyroidism (P = 0.04 vs euthyroid, P = 0.005 vs normal). CONCLUSIONS: The mean result is that after only 30 days of appropriate antithyroid treatment there was an appreciable improvement of exertion capacity.

Effects of histamine on coronary hemodynamics in humans: role of H1 and H2 receptors.

To evaluate whether histamine exerts a direct effect on coronary hemodynamics in humans, and to investigate the role played by H1 and H2 receptors in this response, intracoronary saline solution or histamine (4 micrograms) was administered in 10 patients with normal coronary arteries during diagnostic cardiac catheterization. Histamine injection was repeated after intravenous cimetidine (400 mg) and diphenhydramine (10 mg). The electrocardiogram, arterial pressure and thermodilution coronary blood flow were continuously monitored during and for 40 seconds after each injection. Immediately after histamine injection there was a significant increase in coronary blood flow (65 +/- 6%) and a decrease in coronary vascular resistance (-40 +/- 3%) (both p less than 0.001), with minor changes in the RR interval and the mean arterial pressure. H2 receptor blockade with cimetidine did not affect these changes, while H1 receptor blockade with diphenhydramine significantly reduced the histamine-induced increase in coronary blood flow and the decrease in coronary vascular resistance (26 +/- 6%, p less than 0.005 and -18 +/- 5%, p less than 0.001, respectively). Twenty to 30 seconds after histamine injection, a significant decrease in mean arterial pressure (-17 +/- 2%, p less than 0.001) and in the RR interval (-4 +/- 1%, p less than 0.01) was observed. These changes persisted after H2 receptor blockade with cimetidine, but were completely abolished after H1 receptor blockade with diphenhydramine. In each case coronary and systemic hemodynamics returned to normal within 40 seconds of the injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Freehand three-dimensional echocardiographic evaluation of the effect of telmisartan compared with hydrochlorothiazide on left ventricular mass in hypertensive patients with mild-to-moderate hypertension: a multicentre study.

Antihypertensive efficacy, effects on left ventricular mass index (LVMI) and tolerability of telmisartan, an angiotensin II receptor blocker, were compared with those of hydrochlorothiazide (HCTZ). Adult patients with mild-to-moderate hypertension and an optimal acoustic window by two-dimensional echocardiography were randomised at baseline to 12 months' double-blind, once-daily treatment with telmisartan 80 mg or HCTZ 25 mg. Two-dimensional echocardiography and freehand precordial three-dimensional echocardiography and 24-h ambulatory blood pressure monitoring were performed at baseline and after treatment. Of the 41 telmisartan group patients and 28 HCTZ group patients, 40 and 25, respectively, completed the study. Following treatment, 24-h mean SBP (telmisartan 157 +/- 11 vs 133 +/- 7 mmHg, P<0.001; HCTZ 154 +/- 10 vs 144 +/- 11 mmHg, P<0.003) and DBP (telmisartan 96 +/- 6 vs 83 +/- 5 mmHg, P<0.001; HCTZ 95 +/- 7 vs 87 +/- 8 mmHg, P<0.003) were significantly reduced. Telmisartan produced significantly greater 24-h mean SBP and DBP reductions than HCTZ (P<0.001). LVMI was significantly reduced by telmisartan (141 +/- 16 vs 125 +/- 19 g/m2, P<0.001), but not by HCTZ (139 +/- 20 vs 135 +/- 22 g/m(2)). Incidences of adverse events in both the treatment groups were low; two cases of hypokalaemia occurred with HCTZ. In conclusion, telmisartan 80 mg was well tolerated and significantly reduced SBP, DBP and LVMI after 12 months' treatment compared with HCTZ.

Morpho-functional assessment of interatrial septum: a transesophageal echocardiographic study.

BACKGROUND: Despite the increasing number of reports on lipomatous hypertrophy of interatrial septum, a standardization of measurement of the dimensions of the interatrial septum (IAS) in the different phases of cardiac cycle has not been reported. Moreover, no data on modification of thickness with age and in specific cardiac diseases are available. OBJECTIVE: Our purpose was to study whether the changes of thickness and thinning of IAS may be related to age, left atrial dimension, cardiac cycle and different cardiac diseases. METHODS: 248 patients (mean age 52.7 +/- 19.9 years) underwent transthoracic (TTE) and transesophageal (TEE) echocardiography. IAS was measured at the constant regions anterior and posterior to the fossa ovalis. IAS thickness (tk), thinning (th) and % thinning (% th) were measured. RESULTS: IAS thickness ranged from 4 to 13 mm at the time of ventricular end-systolic phase (mean 6.7 +/- 1.9 mm) and from 6 to 16 mm at the time of atrial systole (mean 9.9 +/- 1.8 mm); significant statistical difference between these values was found (P < 0.01). IAS thinning ranged from 1 to 7 mm (mean 3.42 +/- 1.8) while % IAS thinning from 18 to 76% (mean 36.53 +/- 16.36%). Statistical analysis showed a significant positive correlation between age and ventricular end-systolic thickness and atrial systolic thickness and thinning. An insignificant correlation was found between age and % IAS thinning and between left atrial dimension and IAS tk and th. CONCLUSIONS: Our results demonstrate that IAS thickness increases by age; no correlation exists between IAS thinning and age. There is no difference between IAS thickness and thinning in patients with or without cardiac disease. We believe that the thickness of IAS can be considered hypertrophic only if it exceeds the value of 15 mm during both ventricular end-systolic and atrial systolic phases of the cardiac cycle. IAS thickness and thinning might be an additional parameter to evaluate systolic atrial function particularly with regard to maintenance of synus rhythm after conversion from atrial fibrillation as well as to better understand its role in determining the filling of ventricles in different clinical conditions.

The potential value of transoesophageal evaluation of individual pulmonary venous flow after an atrial baffle procedure.

Following a Mustard's procedure, transoesophageal echocardiography allowed the visualization of all 4 pulmonary veins in 7/12 patients (mean age 14.8 years) and of three veins in a further 2 patients. Both upper pulmonary veins could be visualized consistently. No patient had an isolated pulmonary venous stenosis. In 9 patients in sinus rhythm, computer analysis of Doppler tracings from the left upper pulmonary vein showed significantly lower systolic peak velocities (mean 0.39 +/- 0.10 m/s) and time velocity integrals (mean 6.9 +/- 1.66 cm) than in normal subjects (mean 0.6 +/- 0.09 m/s and 14.4 +/- 2.97 cm respectively; P less than 0.001). We postulate that this is due to compromised atrial relaxation and compliance. In contrast, patients in junctional rhythm (mean 10.7 vs. 7.7 cm in normal subjects). Flow reversal during early ventricular systole (due to tricuspid regurgitation or atrial contraction after retrograde conduction during junctional rhythm) was detected in 6/12 patients. These results confirm that the transoesophageal approach should allow the identification of isolated pulmonary venous obstruction after a Mustard procedure. In addition. detailed analysis of tracings of flow in the pulmonary veins can document the presence of compromised atrial relaxation and help to evaluate the severity of tricuspid regurgitation. It may provide a new index with which to assess impaired systemic ventricular function.

Doppler echocardiographic assessment of left ventricular diastolic function in patients with primary lung cancer treated with doxorubicin.

Eighteen patients were examined by Doppler echocardiography before and after treatment with doxorubicin (DXR). Early left ventricular filling rate decreased from 66 +/- 15 to 51 +/- 10 cm/sec whereas late filling rate increased from 48 +/- 12 to 61 +/- 9 cm/sec (p less than 0.05) with inversion of the E/A ratio suggesting an impairment of left ventricular diastolic function; conversely no significant changes were found in systolic function indexes. These results suggest that follow-up of patients treated with DXR must include left ventricular diastolic function studies. Doppler echocardiography can be successfully used to detect the presence of diastolic abnormalities.

[Bacterial endocarditis due to Erysipelothrix rhusiopathiae. A clinical case report]. / Endocardite batterica da Erysipelotrix rhusiopathiae. Descrizione di un caso clinico.

The authors describe an unusual case of bacterial endocarditis. A very rare etiologic agent, Erysipelothrix rhusiopathiae, was isolated. The patient was not fisherman or butcher and he did ot other risky job. Moreover the disease had an atypical course.

[Clinical value of multiplane transesophageal echocardiography in the diagnosis of lipomatous hypertrophy of the interatrial septum. Report of two clinical cases]. / Utilità clinica dell'ecocardiografia transesofagea multiplanare nella diagnosi di ipertrofia lipomatosa del setto interatriale. Descrizione di due casi clinici.

Lipomatous hypertrophy of interatrial septum is a very rare condition associated with supraventricular arrhythmias and sudden death. The authors describe two clinical cases of lipomatous hypertrophy and underline usefulness of multiplane transesophageal echocardiography in the diagnosis of this affection.

Aortic atheroma. An unknown source of ischemic stroke.

Cerebrovascular mortality represents 25% of all cardiovascular mortality. Defining the pathological mechanism of an episode of ischemic stroke is important for epidemiological, prognostic and overall therapeutic purposes. About 1/4 of ischemic strokes are defined as being of unknown cause. The use of transesophageal echocardiography for studying the aortic arch and thoracic aorta, revealed that aortic atheroma can be considered as an embolic source. Retrospective studies documented a significant prevalence of atheroma >4 mm in the aortic arch in patients with previous stroke (15%); while prospective studies documented an increased risk for cardiovascular events in patients with plaque of =/> 4 mm in thickness at the level of the thoracic aorta compared with controls without these lesions: in particular, the incidence of recurrent stroke is 12%/year, while the incidence of cardiovascular events is 26%. Plaques defined unstable and at risk of embolic event are protrudent, >4 mm in thickness, without calcification and have on their surface mobile thrombus. Embolization from a protrudent atheroma can have a iatrogenic cause, that is cardiac catheterization or placement of an intra-aortic balloon- pump or during cardiopulmonary bypass. The management of the subject with aortic atheroma is not well defined. Encouraging dates with the use of statins are from a recent meta-analysis also anticoagulant treatment versus antiplatelet treatment, reduced incidence of stroke in a significant manner. The surgical therapy of aortic endoarterectomy, has, at this moment, a limited indication, because is not without risk. Transesophageal ecocardiography is a method of choice for the study of the aortic atheroma and it should be done in every patient with stroke by unknown cause.

[Non-invasive evaluation of the endothelial function using high-resolution B-mode ultrasonography]. / Valutazione non invasiva della funzione endoteliale mediante ultrasonografia B-mode ad alta risoluzione.

The vascular endothelium has a central role in regulating vasomotor tone, smooth muscle cell proliferation, platelet and leukocyte adhesion to the arterial wall, thrombosis and fibrinolysis. Disturbances of these endothelial functions have been suggested to be important in the early and advanced phases of atherosclerosis. The development of a simple, valid ultrasound-based method allowed to non-invasively evaluate endothelial function in a large number of individuals with traditional and non-traditional cardiovascular risk factors. The ultrasound technique measures changes in brachial artery diameter in response to an increase in blood flow (reactive hyperemia) and thus in shear stress, which causes endothelium-dependent dilation. This methodology is not yet perfect. The critical issues today involve the definition of "normal values", and standardized scanning and reading protocols to reduce variability.

[Instability determinants of the carotid plaque: from histology to ultrasound]. / Determinanti dell'instabilità della placca carotidea: dall'istologia agli ultrasuoni.

Over the last decade, it has become progressively clear that the most important mechanism responsible for acute coronary and cerebrovascular events is atherosclerotic plaque rupture with superimposed thrombus formation. Anatomo-pathological studies have shown that the risk of rupture depends on plaque type rather than plaque size. The determinants of carotid plaque vulnerability to rupture are similar to those responsible for coronary instability: 1) size and consistency of the lipid-rich atheromatous core, 2) ongoing inflammation and repair processes within the fibrous cap, and 3) the thickness of the fibrous cap covering the core. Unstable plaques contain a soft, lipid-rich core that is covered by a thin and inflamed cap of fibrous tissue. External factors such as mechanical and hemodynamic stresses may be important not only in precipitating disruption of vulnerable plaques, but also in their cellular differentiation. Several imaging techniques have been used to identify plaques at high risk of events. High-resolution B-mode ultrasound is a noninvasive, inexpensive technique which allows a characterization of carotid plaque dimension, internal structure and surface. Nevertheless, such a method is not perfect. The subjective evaluation of plaque morphology on B-mode ultrasound, the need of improving reproducibility and the lack of a uniform terminology are critical issues, which need to be addressed.

Rapid relief of spontaneous angina by intraventricular diltiazem: systemic and regional coronary haemodynamic determinants.

The authors describe a case of spontaneous angina during catheterization in a patient with left anterior descending and circumflex stenosis promptly relieved by diltiazem, 10 mg, given in the left ventricle. Coronary and systemic haemodynamics measured during and at the end of angina demonstrated an increase in blood flow to the ischaemic myocardium as the mechanism responsible for the diltiazem-induced angina relief.

Echo-Doppler evaluation of diastolic filling in differently induced left ventricular hypertrophy.

The study was performed in order to assess whether left ventricular hypertrophy (LVH) (exercise or pressure-overload induced but of a similar extent) may differently affect LV diastolic function. The authors compared LV filling echo-Doppler indexes of 16 male trained rowers (mean left ventricular mass index (LVMI) = 162 +/- 18 g/m2) with those of 34 male patients with secondary LVH, subdivided into two groups according to the extent of LVH (group I, n = 20, with a mean LVMI = 159 + 20 g/m2, and group II, n = 14, with a mean LVMI = 221 +/- 23 g/m2). No abnormalities of LV diastolic filling were observed in the athletes; while in patients with secondary LVH of group I an impairment of the echo-Doppler indexes was detected. A more severe involvement of the diastolic properties was observed in patients with LVH of group II.

Clinical perspectives of intravascular ultrasound.

The history of intravascular ultrasound imaging, recent developments in catheter technology, and the initial in vivo experience are reviewed. Additionally, the article also discusses the potential applications of intravascular ultrasound imaging in coronary and peripheral arterial atherosclerosis, hypertension, pulmonary arterial disorders, valvular heart disease, aortic abnormalities, and in congenital heart disorders. Possible future directions are outlined.

Electrical and mechanical actions of magnesium sulfate during ischemia and reperfusion on isolated perfused rat heart.

Experimental and clinical studies have shown the action of magnesium salts on myocardial tissue and its antiarrhythmic action on digitalis-induced ventricular arrhythmias. We have evaluated the effects of magnesium sulfate (2.5 mM) on heart rate (HR), coronary flow rate (CFR), left ventricular systolic pressure (LVSP), dP/dt max and voltage epicardial electrogram (VEE) during ischemia and reperfusion in isolated perfused rat heart. Forty-five male rats were randomized into 3 groups. In the control group, after a 15 min period of stabilization, hearts were perfused by ischemic perfusion for 30 min and then reperfused. In group I, magnesium sulfate was given after stabilization and before the ischemic period. In group II, calcium concentration was increased by 0.5 mM and magnesium sulfate was given after stabilization and before the ischemic period. In the control group, we observed during ischemia a reduction in HR, CFR, LVSP, dP/dt max and an increase in VEE. In group I, after the administration of magnesium sulfate, we noted a decrease in HR, LVSP, dP/dt max, VEE and during the ischemic period there was no difference in these parameters with respect to the control group. In group II, the increase of extracellular calcium concentration caused an increase in LVSP, dP/dt max and the administration of magnesium sulfate abolished these effect, bringing the values back to basal values. Reperfusion provoked ventricular arrhythmias in 11/15 and 12/15 hearts in the control group and group II respectively, and only 3/15 in group I (p less than 0.005 group I vs control and group II). Thus, our results demonstrated that magnesium sulfate has varied effects on electrical and mechanical parameters and prevents reperfusion arrhythmias according to the hypothesis of a calcium-antagonist mechanism of magnesium.

Transoesophageal echocardiographic evaluation of atrial morphology in children with congenital heart disease.

In a prospective study, atrial morphology was evaluated by both transoesophageal and precordial echocardiography in 86 unoperated children with congenital heart disease (age range = 0.2 to 14.8 years, mean = 3.8 years) to determine what advantages, if any, might be inherent in the transoesophageal approach. The information derived from both ultrasound approaches was correlated and compared to information obtained during subsequent cardiac catheterization (78 patients) and, or, surgical inspection (53 patients). Atrial appendage morphology and hence atrial situs was determined by transoesophageal echocardiography in every case (82 solitus, two right atrial isomerism, two left atrial isomerism). In addition, the transoesophageal approach indicated left juxtaposition in four patients, compared to only one by precordial examination. Probe patency of the foramen ovale was correctly predicted in 21 patients by transoesophageal imaging, but in only 10 by precordial imaging. In two children significant secundum defects, undetected by the precordial route, were identified. Multiple atrial septal defects were correctly defined in four patients by transoesophageal study but in only one by precordial study. Sinus venosus defects were documented in four by the transoesophageal approach, but in only one by the precordial. Primum defects were equally well documented (nine patients) by either technique, but the associated valve leaflet morphology was better documented by transoesophageal study in 5/9. A subtotal cor triatriatum was diagnosed in one child only by transoesophageal investigation. Transoesophageal echocardiography allows a much more detailed evaluation of atrial morphology than precordial imaging even in infants. It provides direct diagnosis of atrial situs, detection of juxtaposed atrial appendages and improved demonstration or definitive exclusion of atrial septal defects.

Direct coronary vasodilator effects of intracoronary histamine administration in humans.

Histamine is widely present in human tissues and can be released by immunologic and nonimmunologic reactions. Although several direct cardiovascular effects of histamine have been demonstrated in humans, little is known about the direct effects of histamine on the human coronary circulation in vivo. Therefore, we investigated the changes in coronary hemodynamics induced by bolus intracoronary administration of 4 micrograms of histamine to 11 patients with angiographically normal coronary arteries under continuous monitoring of R-R interval from the electrocardiogram, arterial pressure (AP), and coronary sinus blood flow (CBF), measured by thermodilution. Immediately after the end of the intracoronary histamine bolus, with R-R interval and AP unchanged, CBF increased from 144 +/- 20 to 238 +/- 27 ml/min (p less than 0.01) and coronary vascular resistance decreased from 0.7 +/- 0.16 to 0.42 +/- 0.1 mm Hg/ml/min (p less than 0.01). No change in coronary hemodynamics was observed after bolus intracoronary administration of physiologic saline. The effects of histamine on systemic hemodynamics consisted of a transient fall in AP and R-R interval, starting after the onset of changes in coronary hemodynamics. These data show that histamine possesses a direct coronary vasodilator effect in humans, independent of the determinants of myocardial oxygen consumption.

The comparative value of exercise echocardiography and 99m Tc MIBI single photon emission computed tomography in the diagnosis and localization of myocardial ischaemia.

To determine the relative value of exercise two-dimensional echocardiography and 99m Tc methoxyisobutylisonitrile single photon emission computed tomography (MIBI SPECT) for the detection of myocardial ischaemia, 103 consecutive patients with either proven or suspected coronary artery disease, who were referred for perfusion scintigraphy, were studied by a combination of the two techniques during the same symptom-limited upright bicycle exercise test. Appropriate echocardiographic images were recorded both at rest and immediately post-exercise and subsequently analysed by means of digital cine loop processing. Both echocardiographic and MIBI SPECT images were visually analysed. For each technique, three different responses to exercise were defined: normal (absence of rest and exercise abnormalities); ischaemic (transient scintigraphic perfusion defects and transient wall motion abnormalities during exercise echocardiography); and fixed abnormalities (fixed scintigraphic perfusion defects; echocardiographic wall motion abnormalities at rest without worsening after exercise). To allow a valid comparison of each technique in localizing ischaemia, the left ventricle was divided into the following six major regions for both methods: anterior, posterolateral, inferior, interventricular septum (subdivided in anterior and posterior septum) and apex. Eleven of the 103 patients had to be excluded from the final analysis because of unsatisfactory examinations: seven with non-interpretable exercise echocardiograms and four with non-interpretable MIBI SPECT images. The response to exercise was concordantly classified by both techniques in 84% of patients (k = 0.78). Exercise echocardiography revealed the presence of ischaemia in 38 and MIBI SPECT in 45 patients (agreement = 77%).(ABSTRACT TRUNCATED AT 250 WORDS)