Luigi Lusiani

Sodium-lithium countertransport and cardiorenal abnormalities in essential hypertension.

The rate of red blood cell sodium-lithium countertransport is elevated only in a subgroup of patients with essential hypertension. We have therefore compared renal and cardiac function and morphology in two groups of hypertensive patients with high (n=23) or normal (n=22) sodium-lithium countertransport (mean±SEM: 0.61±0.10 versus 0.29±0.07 mmol/l red blood cells - hr). The two groups were similar in age, sex distribution, body mass index, smoking habit, duration of hypertension, and actual levels of untreated blood pressure. Hypertensive patients with elevated sodium-lithium countertransport activity showed elevated glomenilar filtration rate (118±2 versus 109±2 ml/min • 1.73 m2;p<0.001), albumin excretion rate (23±3 versus 14±2 /ug/min; p<0.001), larger kidney volume (250±15 versus 203±13 ml • 1.73 m2; p<0.01), lower lithium clearance rate (26.7±03 versus 28.9±03 ml/min • 1.73 m2;p<0.01), and higher total body exchangeable sodium (2,716±33 versus 2,485±41 mmol • 1.73 m2; p<0.01). Left ventricular mass index (139±6 versus 119±6 g/m2; p<0.05), relative wall thickness (0J9±0.05 versus 0.29±0.04 cm;p<0.001), and left posterior wall plus intravenrricular septum thickness (2.02±0.04 versus 1.76±0.03 cm; p<0.05) were also higher in patients with high sodium-lithium countertransport Hypertensive patients with normal sodium-lithium countertransport had renal and cardiac parameters similar to those of a normotensive control group (n=21) except for a higher glomenilar filtration rate and left ventricular mass index. Finally hypertensive patients with elevated rates of sodium-lithium countertransport had significantly higher plasma triglyceride levels and lower plasma concentrations of high density lipoprotein cholesterol. Thus renal and cardiac hypertrophy, lipid abnormalities, and altered kidney function are prominent features of hypertensive patients with higher sodium-lithium countertransport

Prevalence, Clinical Features, and Acute Course of Atypical Myocardial Infarction:

Ninety-four consecutive patients (60 men and 34 women; mean age 68.5 ± 11.5 years) with acute myocardial infarction (MI) were investigated ret rospectively, in order to evaluate the prevalence, clinical features, and short- term course of the atypical forms (symptoms other than chest pain). An atypical MI was found in 30 patients, with a prevalence of 32% (95% confidence limits 27-36%). It was most prevalent in women above sixty-five years old (P < 0.05). Abdominal pain, paroxysmal dyspnea, and pulmonary edema were the most frequent symptoms (33%, 17%, 13%, respectively). No differences were ob served between typical and atypical MI in regard to risk factors (hypercholes terolemia, arterial hypertension, diabetes mellitus, cigarette smoking) and history of MI, cerebrovascular disease, peripheral vascular disease, or chronic lung disease. Significantly fewer patients with atypical MI had a history of an gina pectoris (P < 0.05). No differences were observed in regard to previous medication, except for antiarrhythmic drugs, more often used by atypical pa tients (P < 0.05). Location and severity of MI (as judged by ECG and peak levels of creatine kinase in the serum) were similar in both subgroups, as were the complications (34% typical and 50% atypical) and death rate (12.5% and 16.7%, respectively). In conclusion, atypical MI is not less severe than typical. This emphasizes the need for a high suspicion index in many different clinical settings, but particu larly (although not exclusively) in elderly females, in the presence of abdominal pain or otherwise unexplained paroxysmal dyspnea.

Intimal medial thickening of common carotid artery as indicator of coronary artery disease

The authors investigated the relation between coronary atherosclerosis, angiographically detected, and intimal-medial (I-M) thickening of the common carotid artery (CCA), as measured by high-resolution B-mode ultrasound system. They studied 31 patients with coronary artery disease (CAD) and 23 healthy control subjects. I-M thickening of CCAs and atheromatous plaques at the carotid bifurcation were evaluated. A score system was defined (range 0-20) based on the absence or presence of atherosclerotic lesions at common and internal carotid arteries. A coronary angiography score was defined based on the presence of atherosclerotic lesions at nine coronary arterial segments (range 0-36) . The thickness of CCAs (M ±SD) in CAD patients was significantly higher (1.45 ±0.95 mm) than in controls (0.87 ±0.10 mm, P < 0.005), and an I-M thickening of 1.1 mm or more was specific and positively predictive of CAD. A significant positive correlation between coronary and carotid score was observed (P < 0.028, r=0.373). The study suggests that I-M thickening could be helpful for the identification of patients at risk for CAD.

Noninvasive study of arterial hypertension and carotid atherosclerosis.

We noninvasively evaluated the prevalence and severity of atherosclerotic lesions of the internal carotid artery in 146 nonobese, nondiabetic hypertensive patients who were free of cardiovascular symptoms. We found internal carotid artery disease in 63 patients (43%), 26 (18%) with unilateral disease and the other 37 (25%) with bilateral disease. Disease severity was correlated with age but not duration of hypertension, cholesterol level, or current smoking habit. We also followed disease progression and clinical outcome with respect to cardiovascular events for 3 years in a subgroup of 95 unselected patients. In 20 of the 93 survivors (21.5%) we noted progression of the atherosclerotic lesions that was predicted by neither risk factors nor initial status of the internal carotid artery. New neurologic symptoms developed in four survivors (4%) and symptoms of cardiac ischemia in six (6%). No survivor who developed new cerebrovascular symptoms showed progression of carotid disease. These data provide useful elements for a rational approach to prevention of the atherosclerotic complications of hypertension.

Prevalence of atherosclerotic involvement of the internal carotid artery in hypertensive patients

The prevalence of atherosclerotic involvement of the internal carotid arteries, as diagnosed through an echo-Doppler imaging system with pulsed Doppler spectral analysis was evaluated in 49 hypertensives who had a negative history for neurological symptoms and 49 matched controls. The prevalence was 24.5% in the hypertensive group and 10.2% in the controls with a statistically significant difference (chi-square = 6.07, P less than 0.01). Two hypertensives had severe stenosis (above 50% diameter reduction) and 7 had potentially embolic lesions (irregular surface, inhomogeneous appearance). No one of the matched controls was as severely involved. We conclude that arterial hypertension can account for enhanced prevalence of carotid artery disease in asymptomatic patients.

Wall Thickening of Common Carotid Arteries in Patients Affected by Noninsulin-Dependent Diabetes Mellitus: Relationship to Microvascular Complications:

This study evaluates the wall thickness of common carotid arteries and the atherosclerotic involvement of the carotid bifurcations in patients with noninsulin-dependent diabetes mellitus (NIDDM), with and without microvascular complications. Seventy subjects affected by NIDDM, and 17 healthy controls were evaluated by means of high-resolu tion echo-Doppler scan. Twenty-six diabetics (Group A) had complications (overnight proteinuria > 500 mg, background retinopathy, sensory neuropathy), while 44 (Group B) had no complications. The two groups were comparable for age, sex, plasma lipid profile, and smoking habit. Arterial hypertension was present in 15 of 26 (58%) complicated patients (Group A) and in 18 of 44 (41%) uncomplicated patients (Group B). None of the patients had a history of cerebrovascular disease. The authors found that the wall thickness of the common carotid artery was greater and atherosclerotic lesions of the carotid bifurcation were more frequent in diabetic patients with microvascular complications than in uncomplicated diabetics (who had a similar distribution of other risk factors for atherosclerosis) and in nondiabetic controls. These data on the one hand confirm the role of diabetes as an independent risk factor for carotid atherosclerosis and, on the other hand, indicate a correlation between microvas cular lesions and early atherosclerosis in diabetes.

Immunoscintigraphic Detection of Venous Thrombosis of the Lower Extremities by Means of Human Antifibrin Monoclonal Antibodies Labeled with 111In

A new monoclonal antibody spe cific for the beta-chain of human fi brin (C22A) and labeled with 111In has been obtained and successfully used in rabbits and dogs for the in vivo de tection of venous thrombosis. Studies in humans are currently ongoing. In order to assess the diagnostic value of 111In-antifibrin for the detection of ve nous thrombosis of the lower extrem ities, the authors investigated 25 consecutive patients. Ten patients had clinical and instrumental (con trast phlebography and duplex scan ning) evidence of acute deep venous thrombosis (DVT), 3 had a long standing DVT with relapsing epi sodes of swelling and pain, 5 had superficial venous thrombosis, and the remaining 7 had no signs of thrombosis at all. Twenty patients were being treated with heparin. All patients received 111In-antifibrin at the dose of 74 MBq IV and were scanned with a large field of view gamma camera coupled with a high- energy, parallel-hole collimator at 30 minutes and three, six, and twenty- four hours postinjection. Only the persistence of an abnormal uptake at twenty-four hours confirmed by two observers at visual inspection was considered as positive. A positive result was obtained in 9 of 10 DVT patients (90% sensitivity) and in all SVT patients. The single DVT patient with a negative 111 In- antifibrin test had the longest inter val between scintigraphy and onset of symptoms (fifty-five days). Thus, the age of thrombi represented a sub stantial limitation for the test. A false-positive result was obtained in a single SVT patient, in whom also a deep involvement, unconfirmed by phlebography, was suspected (91.6% specificity). The authors conclude that 111In- antifibrin is a new diagnostic tool for studying deep venous thrombosis, which allows direct imaging of thrombi during their relatively early phase, with a high degree of sensitiv ity and specificity.

Transcutaneous Oxygen Tension (TcPO2) Measurement as a Diagnostic Tool in Patients with Peripheral Vascular Disease

Transcutaneous oxygen tension (TcPO2) was measured through Clarks elec trode at the dorsum of the foot in 52 healthy controls whose ages ranged from twenty to sixty-five years (mean 45.05 ±14.09) and 36 nondiabetic patients with peripheral vascular disease (PVD) (5 stage I, 16 stage II, 4 stage III, 11 stage IV), under standardized conditions at rest and during recovery from limb ische mia obtained with pneumatic cuff compression for 3 minutes. At rest the TcPO2 averaged 71.20±14.26 mm Hg (range 46-92) in the con trols and 51.56±26.38 in the PVD patients (p < .01). A wide overlap was ob served between the two groups and among the different stages of the disease, and consequently, the diagnostic value of TcPO2 at rest was limited (sensitivity equal to 32%). During the recovery from ischemia the time constant (recovery half-time, T½) averaged 38.01±7.23 sec in the controls and 55.84 ± 19.82 in the PVD patients (p < .01). The T½ added to the diagnostic value of the method, making it more sensitive (55%), especially for stage II patients. The TcPO2 at rest was lower with increasing severity of the disease; both the TcPO2 at rest and the T½ correlated with the ankle-arm pressure index in the diseased limbs (r = .48 and - .41 respectively, p < .001). The method showed a limited degree of reproducibility in the controls when the right and the left lower extremity were compared in each subject; in fact, the intrasubject variance of TcPO2 and T½ was of the same magnitude as the intersubject variance (F=1.73 and 1.26 respectively), and the standard devia tions of the difference between lower extremities was elevated (13.32 mm Hg for TcPO2 and 7.80 sec for T½). Moreover, the T½ decreased with increasing age in the controls (r = - .47, p < .001). The authors conclude that, although it is a good indicator of the severity of PVD, the TcPO2 has a limited diagnostic value in this kind of patients, owing to the wide range of normalcy, to the low degree of reproducibility in a single individual, and to the influence of the age factor.

Acromegalic cardiomyopathy. An echocardiography study

Eighteen acromegalic patients (A) and 18 controls without clinical evidence of cardiac involvement and/or endocrine disease (C), matched for sex, age, body surface area, and blood pressure (BP), were investigated by M-mode (2-D derived) echocardiography, to clarify the prevalence and the possible determinants of left ventricular hypertrophy (LVH). Seven patients in each group were hypertensive (BP > 160/95 mmHg). Left ventricular mass (LVM) was 183.1 ± 60.0 g/m2 in A and 130 ± 25.9 g/m2 in C. ALVM above 140 g/m2 (that is the upper normal range in our laboratory) was found in 15/18 A and 2/18 C. The LVH was concentric (h/r > 0.45) in 12/15 A and 1/2 C. Systolic function indexes (% FS, end-systolic stress/end-systolic volume), cardiac index and total peripheral resistance index (as determined by echo) were within the normal range and similar in both groups. No correlationwas found between LVM and BP, LVM and GH plasma levels, LVM and Sm-C levels. A significant correlation was found between LVM and duration of the disease (r 0.44; p<0.05). Our data confirm that LVH is an early and frequent finding in acromegaly. Its prevalence is not entirely accounted for by such factors as body size, BP or increased cardiac output. Metabolic factors may play a major role, and a long lasting exposition to increased GH levels seems the most relevant determinant of LVH.

Percutaneous Excimer Laser Angioplasty of Lower Limb Vessels: Results of a Prospective 24-Month Follow-up

The aim of this prospective study was to assess the effectiveness and the long-term patency effect of excimer laser angioplasty in peripheral arterial obstructive disease. Seventy-eight patients referred for excimer laser angioplasty of lower limbs have been followed up for up to 24 months. Ankle/brachial systolic pressure index, color Doppler mapping, and arterial digital subtraction angiography were performed. Immediate proce dural success was achieved in a high percentage of patients (97%). Balloon angioplasty was also used in 85% of patients. Early reocclusions occurred in 8% of patients. The cumulative patency rate was 47% at the 12-month interval and 40% at the 24-month interval. Poor runoff and the length of the lesions negatively influenced the outcome. Excimer laser angioplasty is an effective procedure, indicated in selected patients showing < 10 cm occlusions and good runoff.