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.

Noninvasive evaluation of left ventricular diastolic function in hypertrophic cardiomyopathy.

Diastolic dysfunction is common in hypertrophic cardiomyopathy (HC). Previous studies suggest that Doppler transmitral flow velocity profiles, and the left atrial (LA) M-mode echogram can be used noninvasively to evaluate left ventricular (LV) diastolic function. However, this has not been proved in HC. In this study we determined the relation of Doppler transmitral flow velocity profiles and the LA M-mode echograms to invasive indexes of LV diastolic function in patients with HC. We studied 25 patients with HC, while off drugs, and calculated LA global and active fractional shortening and the slope of both early and late displacement of the posterior aortic wall during LA emptying by M-mode echocardiography. We calculated peak velocity of early (E) and atrial (A) filling, E to A ratio, and E-wave deceleration time by pulsed Doppler echocardiography, and simultaneous radionuclide angiography, LV pressures, time constant of isovolumic relaxation tau, and the constant of chamber stiffness k by cardiac catheterization. The time constant of isovolumic relaxation tau correlated with the slope of early posterior aortic wall displacement (r = 0.59; p <0.01). LV end-diastolic pressure correlated with global LA fractional shortening (r = -0.75; p <0.001); the constant of chamber stiffness k correlated with active LA fractional shortening (r = -0.53; p <0.02). In a subset of 13 patients, in whom echocardiography and cardiac catheterization were performed simultaneously, similar results were found. LA M-mode recordings provide a more reliable noninvasive assessment of diastolic function in HC than mitral Doppler indexes.

Effects of diltiazem on left ventricular systolic and diastolic function in hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HC) is characterized by impaired diastolic function, and left ventricular (LV) outflow tract obstruction in about one-fourth of patients. Verapamil improves diastolic properties, but may have dangerous adverse effects. This study investigates the effects of diltiazem on hemodynamics and LV function in 16 patients with HC who were studied with cardiac catheterization and simultaneous radionuclide angiography. Studies were performed during atrial pacing (15 beats above spontaneous rhythm) at baseline and during intravenous diltiazem administration (0.25 mg x kg(-1) over 2 minutes, and 0.014 mg x kg(-1) x min(-1). Diltiazem induced a systemic vasodilation (cardiac index: 3.4 +/- 1.0 to 4.0 +/- 1.0 L x min(-1) x m(-2), p = 0.003; aortic systolic pressure: 116 +/- 16 to 107 +/- 19 mm Hg, p = 0.007; systemic resistance index: 676 +/- 235 to 532 +/- 193 dynes x s x cm(-5) x m(-2), p = 0.006), not associated with changes in the LV outflow tract gradient. The end-systolic pressure/volume ratio decreased (30 +/- 42 to 21 +/- 29 mm Hg x ml(-1) x m(-2); p = 0.044). Pulmonary artery wedge pressure (11 +/- 5 to 15 +/- 6 mm Hg, p = 0.006), and peak filling rate increased (4.1 +/- 1.3 to 6.0 +/- 2.4 stroke counts x s(-1), p = 0.004). The time constant of isovolumetric relaxation tau decreased (74 +/- 40 to 59 +/- 38 ms, p = 0.045). The constant of LV chamber stiffness did not change. Thus, active diastolic function is improved by the acute administration of diltiazem by both direct action and changes in hemodynamics and loading conditions. LV outflow tract gradient does not increase despite systemic vasodilation. In some patients, however, a marked increase in obstruction and a potentially harmful elevation in pulmonary artery wedge pressure do occur. Passive diastolic function is not affected.

Effects of dual-chamber pacing in hypertrophic cardiomyopathy on left ventricular outflow tract obstruction and on diastolic function.

Hypertrophic cardiomyopathy (HC) is characterized by impaired diastolic function and, in about 1/4 of patients, left ventricular (LV) outflow tract obstruction. Atrioventricular (AV) pacing diminishes LV outflow tract gradient in HC, but impairs diastolic function in the experimental animal and in different categories of patients. To investigate the effects of AV pacing on hemodynamics and LV function in obstructive HC, 16 patients with HC were studied by cardiac catheterization and simultaneous radionuclide angiography during atrial and AV pacing. The resting LV outflow tract gradient decreased with AV pacing from 60 +/- 34 to 38 +/- 37 mm Hg (mean +/- SD; p <0.001). Regional ejection fraction decreased significantly at the septal level from 0.81 +/- 0.21% to 0.69 +/- 0.27% (p <0.01). Pulmonary artery wedge pressure increased from 10 +/- 5 to 15 +/- 6 mm Hg (p <0.001). AV pacing induced asynchrony (i.e., the coefficient of variation of the time to end-systole increased from 7 +/- 4% to 14 +/- 10% (p <0.01). The time constant of isovolumetric relaxation (t) increased from 58 +/- 24 to 74 +/- 33 ms (p <0.02), and peak filling rate decreased from 491 +/- 221 to 416 +/- 184 ml/s (p <0.05). Thus, AV pacing greatly diminishes resting obstruction through a reduction in septal ejection fraction (i.e., an increase in LV outflow tract width in systole), but impairs active diastolic function and increases filling pressures. These latter effects are potentially detrimental in patients with HC in whom diastolic dysfunction is present.

Amyloid bone disease and highly permeable synthetic membranes.

The effect of different highly permeable membranes on amyloid bone disease (ABD) was retrospectively evaluated in patients on renal replacement therapy (RRT) in our Unit with a dialytic age of more than 4 years. A group of 36 patients (age 60 +/- 12 years) after a variable period (28 +/- 29 months) on hemodialysis with cuprophane membrane (CU-HD), were moved to HDF with a reinfusate volume of 22 +/- 1 1/session, for a period of 65 +/- 26 months using the following membranes: AN69 1.6 m2, PAN 1.8, PMMA 2.1, PS 1.3, polyamide (PA) 1.3 and 1.6. Bone x-rays of wrists, hips and shoulders were taken annually and the presence of ABD was evaluated according to generally accepted criteria. ABD occurred in 4 patients after a period of 73 +/- 30 months on CU-HD only; it developed in 4/7 patients an AN69, in 4/6 on PAN, in 3/5 on PMMA, in 3/5 on PS; no patient of the 13 on PA developed ABD. Comparing patients on PA with those on other synthetic membranes, no significant difference was found in dialysis time (73 +/- 19 vs 83 +/- 28 months) as well as in age (59 +/- 13 vs 61 +/- 11 years) at ABD on set, when present. These data strongly encourage prospective studies enrolling more patients for a longer period of observation in order to evaluate possible differences on ABD development among various synthetic membranes.

Inflammatory markers as predictors of clinical outcome in acute coronary syndromes.

Inflammation is a critical pathogenic component in acute coronary syndromes. As a consequence the potential use of inflammatory markers as predictors of clinical outcome in acute coronary syndromes has been investigated. This review outlines the pathology underlying acute coronary syndromes and reviews the published data on inflammatory markers in acute coronary syndromes.

[Relationship between symptomatology of acute ischemic heart disease and glucose metabolism balance]. / Rapporti tra sintomatologia della cardiopatia ischemica acuta e controllo glicometabolico.

Diabetes mellitus is one of the most important cardiovascular risk factors. An increased prevalence of silent or paucisymptomatic myocardial ischaemia has been described in diabetic patients. The authors examined the relationship between glucose metabolism balance and acute ischemic heart disease symptoms in 174 patients: 46 diabetics and 128 non diabetics. Diagnosis of diabetes mellitus was made during admission to hospital in four patients. No differences of strength, length, type, site and radiation of pain between 46 diabetic patients and 128 non diabetics were found. As regards the other symptoms, the authors found that only dyspnoea and palpitations were prevalent in diabetic patients with ten-year or more-disease length. On the other hand, the prevalence of these two symptoms was not different between non diabetics and diabetics with less than ten-year-disease length.

Lipoma of the heart: a case report.

Lipomas of the heart are rare (only 0.5% according to the Armed Forces Institute of Pathology series) and their diagnosis is often difficult because they are asymptomatic; in fact, in contrast to lipomatous hypertrophy, lipomas are usually found on the epicardial surfaces of the atria or ventricles. In our case, the lipoma was located in both atria and was attached to the interatrial septum involving also the right pulmonary veins, the inferior vena cava and the right phrenic nerve. At histology, the tumor was composed only of mature adipose tissue with entrapped myocytes and vessels. The combination of computed tomography and transesophageal echocardiography allowed a precise diagnosis in terms of the localization and tissue characterization of the tumor.

[Lipoprotein metabolism in arterial walls and its relationship with the genesis of atheromatous lesion]. / Il metabolismo delle lipoproteine nella parete arteriosa e suoi rapporti con la genesi della lesione ateromatosa.

In this review we have concentrated on the ways in which modification of LDL structure may account for foam cell formation. We have presented in vivo evidence as well as in vitro evidence supporting the proposition that modification of native LDL is a prerequisite for foam cell formation and atherogenesis. If further research supports the importance of LDL modification in atherogenesis, a whole new array of possibilities opens itself to us for intervention. At the moment, the only intervention that appears to be feasible is prevention of LDL oxidation; conceivably we might be able to interfere with the aggregation of LDL with itself or with other complexes in the artery wall that appear also to favor initiation of the atherogenic process.

[Hereditary changes of apolipoproteins B and E]. / Alterazioni ereditarie delle apolipoproteine B ed E.

Accelerated atherosclerosis occurs in patients with type III hyperlipoproteinemia and familial hypercholesterolemia. The accumulation of chylomicron remnants of intestinal origin and of VLDL remnants or IDL of hepatic origin observed in type III hyperlipoproteinemia appears to correlate with coronary disease. The presence of defective forms of Apo E prevents normal receptor-mediated catabolism of these lipoproteins. Patients with familial hypercholesterolemia have an elevation of plasma IDL secondary to defective LDL receptors that impair normal catabolism. Familial defective Apo B100 is secondary to an abnormality of Apo B100 that prevents the normal interaction of LDL with the LDL receptor and increases plasma LDL. Macrophages (which are derived from circulating monocytes) have emerged as a key component in atherogenesis because they appear to be progenitors of foam cells in arterial lesions. Macrophages express receptors that recognize chylomicron remnants and VLDL remnants and chemically modified LDL. Thus, in the presence of these specific lipoproteins, macrophages are converted to cells that resemble foam cells.

Heart rate variability in patients with hypertrophic cardiomyopathy: association with clinical and echocardiographic features.

Autonomic dysfunction has been reported in patients with hypertrophic cardiomyopathy. To evaluate the influence of different clinical and echocardiographic features of the disease on sympathovagal balance, as assessed by heart rate variability, 33 patients with hypertrophic cardiomyopathy and 33 healthy volunteers underwent echocardiographic examination and 24-hour electrocardiogram Holter recording. Measures of vagal modulation of heart rate were lower in patients with hypertrophic cardiomyopathy than in controls, particularly in those exhibiting syncope, exertional chest pain, dyspnea, or moderate or severe mitral regurgitation. Furthermore, the age-corrected multiple regression analysis showed that the parasympathetic cardiac control was inversely related to left atrial dimension and directly related to left ventricular end-systolic dimension. Therefore in hypertrophic cardiomyopathy the parasympathetic withdrawal is more evident in patients with symptoms than in those without; the reduction in left ventricular end-systolic dimension and the increase in left atrial size are the echocardiographic features that most influence the sympathovagal balance.