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1.
J Am Coll Cardiol ; 38(7): 2043-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11738313

ABSTRACT

OBJECTIVES: The study was done to define the role of the autonomic nervous system in postoperative tetralogy of Fallot. BACKGROUND: Subsequent to surgical correction of tetralogy of Fallot, patients are at long-term risk of sudden death owing to ventricular electrical instability. The status of the sympathetic nervous system in these patients, known to play an important role in other patients at risk, remains unknown. METHODS: We used (123)I metaiodobenzylguanidine (MIBG) with tomographic imaging, combined with assessment of heart rate variability (HRV), to evaluate the activity of the sympathetic nervous system. We analyzed 22 patients who had undergone total correction of tetralogy of Fallot: 13 with either no or minor ventricular arrhythmias, and 9 with sustained ventricular tachycardia or ventricular fibrillation. RESULTS: Analysis of HRV revealed a reduction in vagal control and sympathetic dominance in all patients compared with a healthy control group of 20 subjects. A significant difference was found in the standard deviation of all the adjacent intervals between normal beats (SDNN) in patients with or without severe ventricular arrhythmias. A significant reduction in uptake of (123)I MIBG was demonstrated 30 min after IV injection, and a trend toward reduction after 5 h, associated with reduced washout indices. These data reflect a decrease in the number of nerve endings in the right and left ventricular walls, and an inhomogeneous distribution of the adrenergic nervous system. The uptake of MIBG was significantly reduced in the patients at risk of ventricular tachycardia or fibrillation. CONCLUSIONS: Subsequent to surgical correction of tetralogy of Fallot, the positive correlation between myocardial uptake of MIBG, SDNN and the QRS dispersion confirmed the usefulness of analysis of the adrenergic nervous system to stratify patients at risk of life-threatening arrhythmias.


Subject(s)
Adrenergic Fibers/physiology , Autonomic Nervous System Diseases/physiopathology , Postoperative Complications/physiopathology , Tachycardia, Ventricular/physiopathology , Tetralogy of Fallot/surgery , Adolescent , Adult , Autonomic Nervous System Diseases/mortality , Child , Child, Preschool , Death, Sudden, Cardiac/epidemiology , Death, Sudden, Cardiac/etiology , Echocardiography, Doppler, Color , Electrocardiography, Ambulatory , Female , Heart Rate/physiology , Humans , Infant , Male , Postoperative Complications/mortality , Prognosis , Risk Factors , Sympathetic Nervous System/physiopathology , Tachycardia, Ventricular/mortality , Tetralogy of Fallot/mortality , Tetralogy of Fallot/physiopathology , Tomography, Emission-Computed, Single-Photon , Ventricular Fibrillation/mortality , Ventricular Fibrillation/physiopathology
4.
J Heart Lung Transplant ; 19(12): 1205-8, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11124491

ABSTRACT

BACKGROUND: Management of cyclosporine (CsA)-associated hyperuricemia in heart transplantation (HT) is difficult. Because of the myelotoxicity of combined allopurinol and azathioprine, we tested sulfinpyrazone. METHODS: We studied 120 HT recipients (109 men; mean age at HT, 52+/-10 years). All had received allopurinol for at least 6 months, which was stopped for 1 month before initiation of sulfinpyrazone. Mean follow-up from HT to onset of sulfinpyrazone (200 mg/day) was 59+/-41 months. We stopped the drug after 6+/-2 months. We compared CsA level and daily dose, serum creatinine, blood urea, and uric acid at onset and before interruption of sulfinpyrazone and, as control, in the last 6 months of allopurinol. RESULTS: Mean uricemia decreased with allopurinol (0.58+/-0.12 vs. 0.41+/-0.07 mmol/liter, p = 0.0001) as well as with sulfinpyrazone (0.51+/-0.13 vs. 0.40+/-0.12 mmol/liter, p = 0.0001). Mean creatinine increased (171+/-42 and 164+/-35 micromol/liter, p = 0.01) with allopurinol, whereas it tended to decrease with sulfinpyrazone (160+/-35 and 154+/-48 micromol/liter, p = NS). Mean urea did not change with allopurinol (14+/-5 vs. 15+/-7 mmol/liter, p = NS), but fell with sulfinpyrazone (14.01+/-5 vs. 12.60 +/-5 mmol/liter, p = 0.0004). Mean CsA levels were constant with allopurinol (193+/-73 vs. 188+/-65 ng/ml, p = NS), although CsA dose was slightly reduced (2.7+/-0.8 vs. 2.6+/-0.8 mg/kg/day, p = 0.007). Conversely, CsA levels dropped with sulfinpyrazone (183+/-89 vs. 121 +/-63 ng/ml, p = 0.0001) despite an increase in CsA daily dose (2.6 +/-0.9 vs. 2.8+/-0.9 mg/kg/day, p = 0.0001). Two subjects were treated for acute rejection. We observed no other side effects. In HT recipients sulfinpyrazone, as an alternative to allopurinol, is effective in achieving metabolic control of hyperuricemia. However, this drug reduced CsA levels, thus the risk of rejection is present.


Subject(s)
Cyclosporine/antagonists & inhibitors , Heart Transplantation , Immunosuppressive Agents/antagonists & inhibitors , Sulfinpyrazone/pharmacology , Uricosuric Agents/pharmacology , Allopurinol/adverse effects , Allopurinol/therapeutic use , Creatinine/blood , Cyclosporine/adverse effects , Cyclosporine/blood , Drug Interactions , Female , Follow-Up Studies , Graft Rejection/therapy , Humans , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/blood , Male , Middle Aged , Risk Factors , Urea/blood , Uric Acid/blood
5.
Int J Cardiol ; 74(1): 67-74; discussion 75-6, 2000 Jun 12.
Article in English | MEDLINE | ID: mdl-10854681

ABSTRACT

We evaluated the utility of positron emission tomography in differentiating patients with idiopathic dilated cardiomyopathy from those with ischemic cardiomyopathy. Twenty consecutive non-diabetic patients with dilatation (end-diastolic volume > or = 120 cc/m2) and reduced systolic function (ejection fraction < or = 40%) of the left ventricle on cineangiography, underwent coronary angiography, F18 fluorodeoxyglucose (F18-FDG) (glucose load technique) and N13-ammonia (N13-NH3) positron emission tomography. A semiquantitative score based on the extension and the severity of the uptake defects was calculated. Endomyocardial biopsy was performed in patients with normal coronary arteries. Ten patients (group A) had normal coronary arteries and histologic features of the endomyocardium fitting with the diagnosis of idiopathic dilated cardiomyopathy. Cineangiography showed critical stenosis of at least one major coronary artery in the other 10 patients (group B). The two groups were similar in age. left ventricular end-diastolic volume and ejection fraction. Both N13-NH3, positron emission tomography and F18-FDG positron emission tomography scores were lower in group A than in group B: 0.1 +/- 0.3 vs. 10.6 +/- 5.1 (P<0.0001) and 2.4 +/- 4.4 vs. 9.9 +/- 4.1 (P<0.0001) respectively. but only N13-NH3 positron emission tomography allowed a complete separation of the two groups (score range 0-1 group A vs. 4-12 group B). The F18-FDG score value showed some overlapping between the two groups (score range 0-12 in the group A vs. 2-17 in the group B). All three idiopathic dilated cardiomyopathy patients with a F18-FDG score value >2 had left bundle branch block on standard ECG. Positron emission tomography imaging with N13-NH3 and F18-FDG provided a complete differentiation between idiopathic dilated cardiomyopathy and ischemic cardiomyopathy patients. However patients with left bundle branch block on ECG could present defects in FDG uptake even if affected by idiopathic dilated cardiomyopathy.


Subject(s)
Cardiomyopathy, Dilated/diagnostic imaging , Coronary Disease/diagnostic imaging , Tomography, Emission-Computed/methods , Adult , Aged , Ammonia , Cardiomyopathy, Dilated/etiology , Coronary Circulation , Coronary Disease/complications , Diagnosis, Differential , Female , Fluorodeoxyglucose F18 , Humans , Male , Middle Aged , Nitrogen Isotopes , Radiopharmaceuticals , Sensitivity and Specificity
6.
Jpn Heart J ; 40(3): 295-309, 1999 May.
Article in English | MEDLINE | ID: mdl-10506852

ABSTRACT

Effective arterial elastance (Ea) is the coupling parameter between the left ventricle and peripheral circulation in normal subjects. If left ventricular end systolic pressure (Pes), contractility (Es) and Ea are known, left ventricular end diastolic volume (LVEDV) and ejection fraction of the ventricle are completely determined. The aim of this study was to give an analytical expression for Ea in patients with mitral and aortic regurgitation, and predict both LVEDV and the effect of vasodilator therapy on LVEDV. Twenty-three subjects with atypical chest pain, 15 patients with mitral insufficiency and 11 with aortic insufficiency underwent diagnostic cardiac catheterization, coronary angiography, and left ventricular cineangiography, which was analyzed quantitatively. Ea was 2.05 +/- 0.63 in normal subjects, while it was 1.28 +/- 0.71 and 1.57 +/- 0.87 in patients with mitral and aortic insufficiency, respectively. All these groups differed with ANOVA test (p = 0.0031). We tested the ability of the analytical expressions for Ea in normal subjects, and patients with mitral insufficiency or aortic insufficiency to predict measured Ea and LVEDV. Ea and LVEDV were predicted rather accurately in every case (p < 0.0001). We used published data to test the effect of resistance modulation on LVEDV. Predicted and measured LVEDV were linearly correlated both in aortic (p < 0.0001) and mitral insufficiency (p = 0.027). Moreover, in some cases a left ventricular enlargement after vasodilator therapy could be anticipated because of an unbalanced decrease in resistance and heart rate. Ea seems to be the coupling parameter between the left ventricle and the peripheral circulation not only in normal subjects, but also in patients with mitral or aortic regurgitation; its measurement before administering vasodilating drugs may be useful in order to predict the effects on LVEDV, and achieve an optimal ventriculoarterial coupling.


Subject(s)
Aortic Valve Insufficiency/physiopathology , Mitral Valve Insufficiency/physiopathology , Myocardial Contraction , Ventricular Function, Left , Aortic Valve Insufficiency/drug therapy , Compliance , Diastole , Heart Rate , Humans , Mitral Valve Insufficiency/drug therapy , Stroke Volume , Vascular Resistance , Vasodilator Agents/therapeutic use , Ventricular Pressure
7.
J Heart Valve Dis ; 8(3): 279-83, 1999 May.
Article in English | MEDLINE | ID: mdl-10399661

ABSTRACT

BACKGROUND AND AIM OF THE STUDY: Although the transvalvular gradient is described as flow-dependent, pressure-dependence of the gradient, irrespective of flow, has not been demonstrated. METHODS: The Sheffield pulse duplicator equipped with a X-Cell 21 porcine valve mounted in the aortic position was used. Transaortic gradient was measured at a constant rate of 80 beats/min, while flow was kept at 2, 5 or 8 l/min, and systemic pressure was increased up to 200 mmHg by adjusting peripheral resistance manually. Valve area was computed with the Gorlin formula. A total of 87 measurements was carried out. RESULTS: For each flow, transvalvular gradient increased linearly with pressure, and computed area decreased. The slope of the pressure-gradient relationship was independent of flow. CONCLUSION: Transaortic gradient depends not only on flow, but also shows pressure-dependency that should be taken into account when evaluating aortic stenosis, especially in hypertensive and hypotensive states.


Subject(s)
Aortic Valve/physiology , Coronary Circulation , Models, Cardiovascular , Pulsatile Flow , Vascular Resistance , Aortic Valve Stenosis/physiopathology , Coronary Circulation/physiology , Humans
8.
Heart ; 81(6): 650-5, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10336927

ABSTRACT

OBJECTIVE: To validate the accuracy of the prognostic significance of non-invasive clinical diagnostic indices as predictors of sustained ventricular tachycardia (sVT) or fibrillation (VF) in patients undergoing repair for tetralogy of Fallot. METHODS: One way analysis of variance and pairwise comparison of the values with the Bonferroni correction, logistic multivariate analysis, and ordinal logistic analysis were used to study quantitative electrocardiographic and echocardiographic variables in 66 patients who had undergone surgery for tetralogy of Fallot by ventriculotomy at a mean (SD) age of 11.8 (9.5) years. The mean (SD) period of follow up was 16.1 (5.7) years after surgery. RESULTS: Four groups of patients were identified by ECG and 24 hour Holter monitoring: 19 (28.7%) without ventricular arrhythmias, 34 (51.5%) with minor ventricular arrhythmias, seven (10.6%) with non-sustained ventricular tachycardia (nsVT), and six (9.0%) with sVT or VF. One way analysis indicated significant differences in QT dispersion (QTd) and end diastolic volume of the right ventricle (EDVRV) among the groups. Univariate logistic analysis showed EDVRV, QTd, and QRS duration to be significantly associated with sVT or VF. Stepwise multivariate analysis and ordinal logistic analysis showed QTd to be preferable to QRS duration as an indicator, because it was unrelated to EDVRV, and was capable of separating different probability curves for nsVT as opposed to sVT or VF. CONCLUSIONS: Stratification of patients undergoing corrective surgery for tetralogy of Fallot and at risk of life threatening arrhythmias is possible by simple and inexpensive means, which provide sensitive and specific indices.


Subject(s)
Postoperative Complications , Tachycardia, Ventricular/etiology , Tetralogy of Fallot/surgery , Ventricular Fibrillation/etiology , Adolescent , Adult , Child , Child, Preschool , Death, Sudden, Cardiac/etiology , Echocardiography, Doppler , Electrocardiography , Female , Follow-Up Studies , Humans , Logistic Models , Male , Postoperative Care/methods , Postoperative Complications/diagnosis , Prognosis , ROC Curve , Regression Analysis , Tachycardia, Ventricular/diagnosis , Ventricular Fibrillation/diagnosis
9.
Muscle Nerve ; 22(4): 473-9, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10204782

ABSTRACT

Mutations in the sarcoglycan genes cause autosomal-recessive muscular dystrophies. Because sarcoglycan genes and their protein products are highly expressed both in skeletal and cardiac muscle, patients with these mutations might be expected to be at risk to develop dilated cardiomyopathy. We therefore studied 13 patients with alpha-, beta-, gamma-sarcoglycan gene mutations by thorough cardiological assessment. Electrocardiographic or echocardiographic abnormalities were observed in about 30% of cases showing a severe course of muscular dystrophy. No correlation was found between the presence of cardiac abnormalities and the type of mutation or sarcoglycan gene involved. The cardiac involvement was never severe, but it may be detected in early stages of the muscle disease. The absence of overt cardiac dysfunction may be due to lower sarcoglycan protein expression in cardiac than skeletal muscle or to less sarcolemmal instability at the myocardial level, possibly related to the different distribution of forces generated by contraction of the myocardium with respect to proximal limb-girdle muscles.


Subject(s)
Cytoskeletal Proteins/genetics , Heart/physiology , Membrane Glycoproteins/genetics , Muscular Dystrophies/genetics , Adolescent , Adult , Blotting, Western , Child , Child, Preschool , Female , Genes, Recessive , Humans , Immunohistochemistry , Male , Middle Aged , Mutation , Phenotype
11.
Am J Cardiol ; 82(4): 433-7, 1998 Aug 15.
Article in English | MEDLINE | ID: mdl-9723629

ABSTRACT

Adjusted-dose warfarin is effective for stroke prevention in patients with nonrheumatic atrial fibrillation (AF), but the risk of bleeding is high, especially among the elderly. Fixed minidose warfarin is effective in preventing venous thromboembolism with low risk of bleeding and no need for frequent clinical monitoring. Patients > 60 years with nonrheumatic AF were randomized in an open-labeled trial to receive fixed minidose warfarin (1.25 mg/day) or standard adjusted-dose warfarin (International Normalized Ratio [INR] between 2.0 and 3.0). Primary outcome events were ischemic stroke, peripheral or visceral embolism, cerebral or fatal bleeding, and vascular death. Secondary end points were major bleeding, myocardial infarction, and death. This study was discontinued before completion in light of publication of the Stroke Prevention in Atrial Fibrillation III trial, which indicated that low-intensity fixed-dose warfarin treatment (i.e., INR < 1.5) was insufficient for stroke prevention in high-risk patients with nonrheumatic AF. From a total of 1,209 considered patients, 303 were randomized to be studied (150 in the minidose group and 153 in the adjusted-dose group). Mean follow-up was 14.5 months. The rate of cumulative primary events was 11.1% (95% confidence intervals [CI] 4.0 to 18.2) in the fixed minidose group and 6.1% (95% CI 1.1 to 11.1) in the adjusted-dose group (p = 0.29). The rate of ischemic stroke was significantly higher in the minidose group (3.7% vs 0% per year, p = 0.025). Major bleedings were more frequent in standard treatment group (2.6% vs 1% per year, p = 0.19). Most thromboembolic complications occurred at INRs < 1.2, whereas the majority of hemorrhages occurred at INRs > 3.0. No significant difference in primary outcome events was observed in the abbreviated study. However, the significantly increased occurrence of ischemic stroke in the fixed minidose warfarin group suggests that this regimen does not protect patients with nonrheumatic AF.


Subject(s)
Anticoagulants/administration & dosage , Atrial Fibrillation/drug therapy , Intracranial Embolism and Thrombosis/prevention & control , Warfarin/administration & dosage , Aged , Aged, 80 and over , Atrial Fibrillation/complications , Disease-Free Survival , Female , Humans , International Normalized Ratio , Intracranial Embolism and Thrombosis/etiology , Male , Middle Aged , Treatment Outcome
12.
Am J Cardiol ; 81(12A): 36G-40G, 1998 Jun 18.
Article in English | MEDLINE | ID: mdl-9662226

ABSTRACT

Sustained inotropic stimulation, such as dobutamine infusion, has the potential to cause an additional contractile deterioration in viable but chronically hypoperfused and dysfunctioning myocardium, by inducing ischemia. Postextrasystolic potentiation (PESP) represents a potent inotropic stimulus without risk of provoking ischemia, as it is instantaneous. In this study, we assessed the role of PESP-echocardiographic examination in predicting the recovery of regional contractility after coronary revascularization. We examined 105 consecutive patients with multivessel coronary artery disease who were candidates for bypass surgery; 79 were included in this prospective study. Preoperative reversibility of contractile dysfunction in asynergic myocardial regions was determined by PESP, with a coupling interval of 500 msec decreasing to 300 msec, with a progressive decrease by 10 msec. The examination was accompanied by continuous 2-dimensional (2D) echocardiographic monitoring. The assessed sensitivity and specificity were 92% and 87%, respectively; the predictive accuracy was 90%. These results demonstrated that PESP echocardiography is a useful and cost-effective method for identifying viable myocardium in patients undergoing myocardial revascularization.


Subject(s)
Coronary Disease/surgery , Echocardiography, Doppler/methods , Myocardial Revascularization , Ventricular Dysfunction/diagnostic imaging , Adult , Aged , Coronary Disease/diagnostic imaging , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Prognosis , Prospective Studies , Sensitivity and Specificity
13.
J Am Coll Cardiol ; 31(2): 404-12, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9462586

ABSTRACT

BACKGROUND: Insulin-dependent diabetes mellitus (IDDM) is associated with an increased incidence of heart failure due to several factors, and in some cases a specific cardiomyopathy has been suggested. OBJECTIVES: This study sought to assess the mechanisms of exercise-induced left ventricular (LV) dysfunction in asymptomatic patients with IDDM in the absence of hypertensive or coronary artery disease. METHODS: Fourteen consecutive patients with IDDM were enrolled (10 men, 4 women; mean [+/- SD] age 28.5 +/- 6 years); 10 healthy subjects matched for gender (7 men, 3 women) and age (28.5 +/- 3 years) constituted the control group. LV volume, LV ejection fraction (LVEF) and end-systolic wall stress were calculated by two-dimensional echocardiography at rest and during isometric exercise. LV contractile reserve was assessed by post-extrasystolic potentiation (PESP) obtained by transesophageal cardiac electrical stimulation and dobutamine infusion. Myocardial iodine-123 metaiodobenzylguanidine (MIBG) scintigraphy was performed to assess adrenergic cardiac innervation. RESULTS: Diabetic patients were classified into group A (n = 7), with an abnormal LVEF response to handgrip (42 +/- 7%), and group B (n = 7), with a normal response (72 +/- 8%). Baseline LVEF was normal in both group A and B patients (60 +/- 6% vs. 61 +/- 7%, p = NS). In group A patients, the LV circumferential wall stress-LVEF relation showed an impairment in LVEF disproportionate to the level of LV afterload. No significant changes in LVEF occurred during dobutamine (60 +/- 6% vs. 64 +/- 10%, p = NS), whereas PESP significantly increased LVEF (60 +/- 6% vs. 74 +/- 6%, p < 0.001); PESP at peak handgrip normalized the abnormal LVEF (42 +/- 7% vs. 72 +/- 5%, p < 0.001); and MIBG uptake normalized for body weight or for LV mass was lower than that in normal subjects (1.69 +/- 0.30 vs. 2.98 +/- 0.82 cpm/MBq per g, p = 0.01) and group B diabetic patients (vs. 2.79 +/- 0.94 cpm/MBq per g, p = 0.01). Finally, a strong linear correlation between LVEF at peak handgrip and myocardial MIBG uptake normalized for LV mass was demonstrated in the study patients. CONCLUSIONS: Despite normal contractile reserve, a defective blunted recruitment of myocardial contractility plays an important role in determining exercise LV dysfunction in the early phase of diabetic cardiomyopathy. This abnormal response to exercise is strongly related to an impairment of cardiac sympathetic innervation.


Subject(s)
Adrenergic Fibers/physiology , Diabetes Mellitus, Type 1/physiopathology , Heart Conduction System/physiopathology , Ventricular Dysfunction, Left/physiopathology , 3-Iodobenzylguanidine , Adrenergic Fibers/diagnostic imaging , Adrenergic beta-Agonists , Adult , Body Weight , Cardiac Complexes, Premature/physiopathology , Cardiac Output, Low/etiology , Cardiac Volume/physiology , Cardiomyopathies/etiology , Cardiomyopathies/physiopathology , Case-Control Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/diagnostic imaging , Dobutamine , Echocardiography , Electric Stimulation , Exercise , Female , Hand Strength , Heart Conduction System/diagnostic imaging , Humans , Incidence , Linear Models , Male , Myocardial Contraction/physiology , Physical Exertion , Radionuclide Imaging , Radiopharmaceuticals , Rest , Stroke Volume/physiology , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/etiology , Ventricular Function, Left/physiology
14.
Neuromuscul Disord ; 8(8): 585-90, 1998 Dec.
Article in English | MEDLINE | ID: mdl-10093066

ABSTRACT

We report here for the first time the case of a symptomatic DMD carrier, who had a heart transplant for a severe dilated cardiomyopathy. Dystrophin immunohistochemistry, western blot and analysis of X-chromosome inactivation on leucocytes, and skeletal and cardiac muscle biopsies on the explanted heart were performed. The patient was a heterozygote for exons 50-52 deletion in the dystrophin gene. The number of dystrophin-deficient fibres in the heart was much higher than in skeletal muscle. On the other hand, the explanted heart showed a non-skewed pattern of X-chromosome inactivation, as in leukocytes and skeletal muscle. The adverse cardiac course may be explained by the absence of regeneration among cardiomyocytes.


Subject(s)
Cardiomyopathy, Dilated/surgery , Heart Transplantation , Heterozygote , Muscular Dystrophies/complications , Muscular Dystrophies/genetics , Adult , Biopsy , Cardiomyopathy, Dilated/complications , Cardiomyopathy, Dilated/metabolism , Cardiomyopathy, Dilated/pathology , DNA/analysis , Dosage Compensation, Genetic , Dystrophin/genetics , Dystrophin/metabolism , Female , Humans , Immunohistochemistry , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Muscular Dystrophies/metabolism , Muscular Dystrophies/pathology , Myocardium/metabolism
15.
Circulation ; 96(3): 816-20, 1997 Aug 05.
Article in English | MEDLINE | ID: mdl-9264487

ABSTRACT

BACKGROUND: Identification of viable but hibernating myocardium remains a relevant issue in the current era of myocardial revascularization. Echocardiography can be helpful in detecting reversible contractile dysfunction and optimizing the selection of patients for coronary bypass surgery. METHODS AND RESULTS: Eighty-four consecutive candidates for bypass surgery with chronic multivessel coronary artery disease were screened, and 60 were included in this prospective study. Preoperative evaluation of a reversible contractile dysfunction in asynergic myocardial regions was performed by dobutamine infusion at 5 (low dose) and 10 (intermediate dose) microg x kg(-1) x min(-1) with each stage lasting at least 5 minutes; postextrasystolic potentiation (PESP), with a coupling interval ranging from 500 to 300 ms with a progressive 10-ms decrease; or a combination of both dobutamine infusion and PESP. Sensitivity (92% versus 86%) and predictive accuracy (89% versus 84%) were higher with PESP than dobutamine (P=.009 and P=.001, respectively), but the combination did not improve sensitivity or accuracy. Dobutamine induced ischemic dysfunction in 15% of patients at the intermediate dose; however, the low dose resulted in loss of sensitivity. CONCLUSIONS: PESP echocardiography is a useful and cost-effective method to identify viable myocardium in patients with multivessel coronary disease undergoing revascularization and is more sensitive and accurate than dobutamine infusion.


Subject(s)
Cardiac Complexes, Premature/diagnostic imaging , Cardiac Complexes, Premature/physiopathology , Cardiotonic Agents , Coronary Artery Bypass , Dobutamine , Echocardiography , Heart/physiopathology , Adult , Aged , Female , Follow-Up Studies , Forecasting , Humans , Male , Middle Aged , Myocardial Contraction , Postoperative Period , Prospective Studies , Treatment Outcome
16.
Int J Cardiol ; 60(1): 7-13, 1997 Jun 27.
Article in English | MEDLINE | ID: mdl-9209933

ABSTRACT

The presence of myocardial injury during non-surgical coronary revascularization has been evaluated by means of highly specific and sensitive biochemical markers. Troponin T, creatine kinase-MB isoenzyme mass concentration, and creatine kinase MB2/MB1 isoform ratio have been determined in 80 patients who underwent coronary revascularization with percutaneous transluminal coronary angioplasty (PTCA). Forty-five patients underwent balloon angioplasty, 15 rotational atherectomy, 10 directional atherectomy, and 10 elective coronary stenting. Serum concentration of the evaluated markers did not increase significantly after 57 uncomplicated revascularization procedures, including 15 rotablation procedures, nor after 8 PTCAs complicated by localized coronary type B and C dissections. Significant elevation of all markers above the upper limits of the reference interval (P < 0.05) was detected after occlusion of small side branches (< 0.5 mm diameter) in 5 patients. Creatine kinase MB2/MB1 isoform ratio was the earliest marker to increase. After recanalization of occluded vessels in 8/10 patients with 6-60 days old myocardial infarction only troponin T concentrations increased from a baseline of 0.28 microgram/l to a median peak of 0.80 microgram/l. This increase was statistically not significant (P = 0.12). In conclusion, myocardial damage was not detected following uncomplicated non-surgical revascularization obtained with different techniques. Markers of myocardial injury provide high sensitivity after small side branch occlusion.


Subject(s)
Angioplasty, Balloon, Coronary/adverse effects , Atherectomy, Coronary/adverse effects , Creatine Kinase/blood , Myocardium/metabolism , Troponin/blood , Aged , Biomarkers , Enzyme-Linked Immunosorbent Assay , Female , Humans , Isoenzymes , Male , Middle Aged , Sensitivity and Specificity , Statistics, Nonparametric , Troponin T
18.
Thromb Haemost ; 77(5): 839-44, 1997 May.
Article in English | MEDLINE | ID: mdl-9184389

ABSTRACT

BACKGROUND: The long-term administration of oral anticoagulants to patients with mechanical heart valve prostheses is generally accepted. However, the appropriate intensity of oral anticoagulant treatment in these patients is still controversial. METHODS AND RESULTS: From March 1991 to March 1994, patients referred to the Padova Thrombosis Center who had undergone mechanical heart valve substitution at least 6 months earlier were randomly assigned to receive oral anticoagulants at moderate intensity (target INR = 3) or moderate-high intensity (target INR = 4). Principal end points were major bleeding, thromboembolism and vascular death. Minor bleeding was a secondary end-point. A total of 104 patients were assigned to the target 3 group and 101 to the target 4 group; they were followed for from 1.5 years to up 4.5 years (mean, 3 years). Principal end-points occurred in 13 patients in the target 3 group (4 per 100 patient-years) and in 20 patients in the target 4 group (6.9 per 100 patient-years). Major hemorrhagic events occurred in 15 patients, 4 in the target 3 group (1.2 per 100 patient-years) and 11 in the target 4 group (3.8 per 100 patient-years) (p = 0.019). The 12 recorded episodes of thromboembolism, 4 of which consisted of a visual deficit, were all transient ischemic attacks, 6 in the target 3 group (1.8 per 100 patient-years) and 6 in the target 4 group (2.1 per 100 patient-years). There were 3 vascular deaths in each group (0.9 and 1 per 100 patient-years for target 3 and target 4 groups, respectively). Minor bleeding episodes occurred 85 times (26 per 100 patient-years) in the target 3 group and 123 times (43 per 100 patient-years) in the target 4 group (p = 0.001). CONCLUSIONS: Mechanical heart valve patients on anticoagulant treatment who had been operated on at least 6 months earlier experienced fewer bleeding complications when maintained on a moderate intensity regimen (target INR = 3) than those on a moderate-high intensity regimen (target INR = 4). The number of thromboembolic events and vascular deaths did not differ between the two groups.


Subject(s)
Anticoagulants/therapeutic use , Heart Valve Prosthesis , Administration, Oral , Adult , Aged , Anticoagulants/administration & dosage , Anticoagulants/adverse effects , Dose-Response Relationship, Drug , Female , Follow-Up Studies , Heart Valve Prosthesis/mortality , Hemorrhage/chemically induced , Hemorrhage/epidemiology , Humans , Ischemic Attack, Transient/chemically induced , Ischemic Attack, Transient/epidemiology , Male , Middle Aged , Thromboembolism/chemically induced , Thromboembolism/epidemiology
19.
Clin Cardiol ; 20(4): 333-6, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9098590

ABSTRACT

The purpose of this paper is to review the history of the clinico-pathologic investigations performed at the University of Padua on an old morbid entity ("parchment heart"), which, in the 1960s, led to the clinical description of the disease, in the 1980s to the revival of the scientific interest, and in the mid 1990s to the understanding of the genetic background. All the steps of the progressive knowledge are reviewed: necropsy of young people who died suddenly, in vivo diagnosis by ECG, echocardiography, angiocardiography, endomyocardial biopsy, nuclear magnetic resonance, and diagnostic criteria. Familial occurrence with autosomic dominant transmission and various penetrance was documented. Gene defects were recently mapped both to chromosome 14q23-q24 and 1q42-q43, thus providing evidence for genetic heterogeneity. The pathologic substrates of arrhythmogenic right ventricular cardiomyopathy pointed to an acquired progressive myocardial atrophy with fibro-fatty replacement of dying myocytes. Nowadays the disease is definitively regarded as a primary myocardial disorder and it has been included in the revised WHO classification of cardiomyopathies.


Subject(s)
Cardiomyopathies/history , Ventricular Dysfunction, Right/history , Arrhythmias, Cardiac/etiology , Arrhythmias, Cardiac/history , Cardiomyopathies/classification , Cardiomyopathies/genetics , Chromosomes, Human, Pair 1 , Chromosomes, Human, Pair 14 , Death, Sudden, Cardiac/etiology , Genes, Dominant , History, 20th Century , Humans , Italy , Ventricular Dysfunction, Right/classification , Ventricular Dysfunction, Right/genetics
20.
G Ital Cardiol ; 27(4): 323-7, 1997 Apr.
Article in Italian | MEDLINE | ID: mdl-9244737

ABSTRACT

INTRODUCTION: Heart transplantation (HT) is a largerly accepted therapy for patients with refractory congestive heart failure. However, lack of donors imposes a rigorous choice among candidates for transplantation. Aim of this study was to identify retrospectively determinants for the selection of recipients. METHODS: Between december 1985 and december 1993 500 patients were listed for HT at the Department of Cardiovascular Surgery of the Padua University. Among United Network for Organ Sharing (UNOS) status II patients, 42 transplanted (group I) and 38 died waiting for a donor (group II) were chosen. The following parameters were collected at the time of insertion into the waiting list: sex, blood group, diagnosis, age, body surface area, natriemia, renal function, hepatic function, presence of ventricular arrhythmias, use of ACE-inhibitors, cardiac index, mean pulmonary pressure, mean wedge pressure, mean arterial pressure, central venous pressure, pulmonary arteriolar resistances, left ventricular ejection fraction. Also the time on waiting list until a final event (transplantation or death) was considered. RESULTS: Comparing the two groups the diagnosis of dilated cardiomyopathy (59.4% group I vs 36.8% group II; p = 0.04) and ejection fraction (26.4 +/- 9.1% group I vs 22.2 +/- 8.0% group II; p = 0.03) were the only variables statistically different. Multivaried analysis evidenced some parameters as independent predictors for HT. In detail, being listed for HT for more than 6 months lowered the probability to receive a heart to 0.34, while waiting for more than 12 months increased it to 2.64. Mean arterial pressure higher than 75 mmHg increased the probability for HT to 2.87, while an increase in mean pulmonary pressure of 5 mmHg lowered the probability to 0.80. An increase in the cardiac index of 0.5 l/m1/m2 lowered the probability to 0.61. A blood group other than 0 increased the possibility to 3.60, the basal surface area higher than 1.78 m2 lowered it to 0.306 and an ejection fraction higher than 22% increased it to 3.94. CONCLUSIONS: We can conclude that parameters which predict the outcome of patients listed for HT were not only size matching, blood group and waiting time, but also ejection fraction, arterial pressure and diagnosis.


Subject(s)
Heart Transplantation , Patient Selection , Adult , Aged , Female , Heart Diseases/mortality , Heart Diseases/physiopathology , Heart Diseases/surgery , Hemodynamics/physiology , Histocompatibility Testing , Humans , Italy , Male , Middle Aged , Retrospective Studies , Tissue Donors
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