Marco Comeglio

Prognostic value of 6‐minute walk corridor test in patients with mild to moderate heart failure: comparison with other methods of functional evaluation

The study was designed to evaluate the prognostic value of the 6‐min walk test (6MWT) in patients with mild to moderate congestive heart failure (CHF).

Diagnostic accuracy of peak exercise echocardiography in coronary artery disease: Comparison with thallium-201 myocardial scintigraphy

To evaluate the accuracy of exercise two-dimensional echocardiography for the recognition of coronary artery disease, 53 patients (46 men and 7 women, age range 35 to 69 years) without either previous myocardial infarction or resting wall motion abnormalities, were studied. According to coronary angiography 26 had normal coronary arteries, 14 had one-vessel, seven had two-vessel, and six had three-vessel disease. After withdrawal of any therapy, all patients underwent a single exercise stress test with a stress table during which cine-loop digitized echocardiography was acquired and 74 MBq of thallium-201 (TI-201) were injected. Echocardiographic images were evaluated at rest and at peak exercise. Three-view planar scintigraphic images were collected immediately after exercise and 4 hours later. For the overall recognition of coronary artery disease, exercise electrocardiography had 77.8% sensitivity and 65.4% specificity; myocardial scintigraphy had 100% sensitivity and 92.3% specificity; and exercise echocardiography had 92.6% sensitivity and 96.2% specificity (both NS versus myocardial scintigraphy). Global accuracy was 71.7% for exercise electrocardiography, 94.3% for stress echocardiography, and 96.2% for myocardial scintigraphy. For the classification of the individual involved coronary arteries, the sensitivity of myocardial scintigraphy was 84.8% and that of exercise echocardiography was 63% (p less than 0.01); the related specificities were 98% and 98.2% respectively (NS). It may be concluded that exercise echocardiography is highly accurate for the recognition of coronary artery disease, whereas it appears less sensitive in the identification of the involved vessels, particularly in patients with multivessel disease.

Low protein Z plasma levels are independently associated with acute coronary syndromes

Protein Z (PZ) is a single chain vitamin-K-dependent glycoprotein synthesized by the liver. Studies in vivo and in vitro suggest that PZ plays an important role in inhibiting coagulation as it serves as cofactor for the inactivation of factor Xa by forming a complex with the plasma PZ-dependent protease inhibitor. Recently, conflicting findings on plasma PZ levels in patients with ischemic stroke have been published. Aim of our study was to investigate the role of PZ in acute coronary syndromes (ACS). PZ plasma levels were determined in 223 (189 M; 34 F) patients with ACS referring to the Coronary Intensive Therapy Unit of University of Florence and in 265 (219 M; 46 F) healthy subjects. Patients under oral anticoagulation treatment as well as subjects with positivity for antiphospholipid antibodies were excluded. None had liver or kidney dysfunction. The mean PZ plasma level was lower in patients (1508 +/- 730 ng/mL) than in controls (1728 +/- 594 ng/mL) (p < 0.0001). PZ levels below the 5th percentile (565 ng/mL) of normal values distribution in control subjects were found in 15.7% of patients and in 4.9% of controls (p <0.0001). At multivariate analysis, PZ levels below 565 ng/mL were associated with ACS (OR=3.3; 99%CI 1.1-9.7; p = 0.004). The contemporary presence of low PZ levels and smoking habit leads to an increased risk of ACS (OR=9.5; 99%CI 2.4-37.2; p < 0.0001). In conclusion, our results suggest a possible role of PZ in the occurrence of arterial thrombosis.

Comparison of different methods of functional evaluation in patients with chronic heart failure

Stratification of the severity of heart failure has major prognostic and therapeutic implications.

Clinical expression of coronary artery ectasia.

Objective Coronary artery ectasia (CAE) is an uncommon finding at cardiac catheterisation. Our objective was to retrospectively assess the angiographic prevalence of CAE and its clinical expression. Methods From January 1999 to June 2001, 3870 consecutive patients underwent coronary angiography at our catheterisation laboratory. Results The prevalence of CAE was 3.6%. Most patients were male (89.2%). Type 1 CAE was observed in 20% of patients, type 2 in 11%, type 3 in 43%, and type 4 in 26%. The right coronary artery was most commonly involved (75%). In 55 patients with acute myocardial infarction, CAE within the culprit vessel was found in 32 patients (58.1%): ectasia was associated with stenosis in 29 patients, whereas isolated CAE was observed in only three patients. In 23 patients (41.8%), CAE was detected as a collateral finding in the presence of the culprit occluded, non-ectatic vessel. Overall, in the 109 patients (78%) with acute coronary syndrome, the culprit lesion was found to be related to the ectatic vessel in 46 patients (33.1%): ectasia was associated with stenosis in 39 patients, whereas isolated CAE was observed in only seven patients. In 66.9% CAE was an incidental finding on angiography. At follow-up, three patients with CAE died (2%). Conclusions In our investigation, the angiographic prevalence of CAE was 3.6%. CAE occurred predominantly in males and more often affected the right coronary artery. It was associated with acute coronary syndrome in one third of cases. Isolated CAE was associated with a good prognosis at follow-up.

Timing, setting and incidence of cardiovascular complications in patients with acute myocardial infarction submitted to primary percutaneous coronary intervention

BACKGROUND At the Istituto di Clinica Medica Generale e Cardiologia (Florence, Italy), the widespread use of percutaneous coronary intervention (PCI) has markedly changed the hospital course of patients with acute myocardial infarction (AMI). These patients are typically transferred to the coronary care unit (CCU) only after primary PCI, whereas during the thrombolytic era, patients were first admitted to CCU before reperfusion. OBJECTIVES AND METHODS The incidence, timing and setting of complications from symptom onset to hospital discharge in 689 consecutive AMI patients undergoing PCI were evaluated. RESULTS Ventricular fibrillation occurred in 11% of patients, and most episodes (94.7%) occurred before or during PCI. Of all patients, 6.3% developed complete atrioventricular block (CAVB), and in 86.3% of these cases, the CAVB occurred before or during PCI; in 94.5%, a CAVB resolution occurred in the catheterization laboratory (CL). Thirty-one patients (4.5%) had impending shock on admission to the CL. Cardiogenic shock developed in 2 9 patients (4.2%), mostly in the prehospital phase or in the CL. Only four patients (less than 1%) developed cardiogenic shock later during their hospital course. Similarly, circulatory and ventilatory support, as well as temporary pacing and cardiac defibrillation, were used mostly in the prehospital phase or in the CL. During the CCU stay, 45 patients (6.5%) had hemorrhagic or vascular complications, and the incidence of post-PCI ischemia and early reocclusion of the culprit vessel were low (2.1% and 0.6%, respectively). Thus, cardiac complications usually associated with AMI were observed mainly before hospital admission or in the CL during the reopening of the target vessel. These complications were rarely observed after a successful PCI. CONCLUSIONS For AMI patients, the CL is not only the site of PCI, it is also where most life-threatening cardiac complications are observed and treated.

Decreased Baroreflex Sensitivity Assessed from Phase IV of Valsalva Maneuver in Mild Congestive Heart Failure

Decreased sensitivity of cardiopulmonary and arterial baroreceptors has been hypothe sized to sustain sympathetic activation in patients with heart failure. In the present inves tigation the relationship between the impairment of baroreflex sensitivity and clinical severity of congestive heart failure was investigated. The authors studied 58 patients with heart failure (14 in NYHA class I, 22 in NYHA class II, and 22 in NYHA class III), 38 women and 20 men, age range 28-65 years. Thirty-two patients suffered from idiopathic dilated cardiomyopathy and 26 from coronary heart disease. As control group they examined 21 age-matched subjects. Baroreceptor sensitivity was studied by using the Valsalva maneuver as stimulus. Arterial pressure and heart rate were measured nonin vasively by Finapres instrument (Ohmeda) and signals were recorded and elaborated with a personal computer. A decrease of baroreflex sensitivity was already demonstrable in NYHA class I patients (4.72 ±3.31 vs 9.25 ±5.05 msec/mm Hg in control group) (p < 0.005). A further impairment of baroreceptor response was found in patients in NYHA class II (1.94 ±2.88 msec/mm Hg, p < 0.001) and class III (1.78 ±1.52 msec/mm Hg, p < 0.001). Baroreceptor response showed a significant correlation with functional NYHA class (r = 0.61, p < 0.001) and anaerobic threshold (r = 0.57, p < 0.001) while the correlation was less tight with left ventricular end-diastolic diameter, fractional short ening, left ventricular ejection fraction, pulmonary mean arterial blood pressure, cardiac index, distance at 6 minutes walk corridor test, and maximal oxygen consumption (VO 2max). These results suggest that baroreceptor function may be impaired early in the clinical course of heart failure and may contribute to sympathetic activation.

Left Atrial Size Changes in Patients with Paroxysmal Lone Atrial Fibrillation: An Echocardiographic Follow-up

Left atrial enlargement has been demonstrated to occur as a consequence of the arrhythmia in patients with chronic atrial fibrillation (AF) in the absence of organic heart disease, whereas contrasting results have been reported in patients with paroxysmal lone AF. In the present investigation the behavior of left atrial size was followed up for an average period of 30.3 months in 20 patients with paroxysmal lone AF since their first arrhythmic episode. No significant changes in left atrial size were found at the end of the follow-up period. In 65% of patients the arrhythmia recurred at least once yearly. Left atrial size at enrollment was not significantly different in these patients from those without recurrences and did not change in either group during follow-up. The results suggest that in patients with lone AF left atrial dilatation occurs only after the arrhythmia becomes chronic. Early restoration of sinus rhythm may interrupt the vicious circle leading to atrial enlargement.

Contrast-induced nephropathy in urgent coronary interventions.

Objectives Patients submitted to urgent percutaneous coronary interventions (PCIs) are quite often at high risk for contrast-induced nephropathy (CIN) since they exhibit several predisposing factors such as electrical and haemodynamic instability together with the lack of time to undergo adequate prophylaxis. This was a not blinded, non-randomized study whose aims were (i) to evaluate the incidence of CIN after urgent PCI in a high-volume cardiovascular referral practice (patients with acute myocardial infarction or with acute coronary syndromes enrolled in a single centre), and (ii) to assess the prognostic implications of CIN during hospitalization and at 1-month follow-up. Methods Between 1 October 2003 and 1 April 2004, 194 consecutive patients undergoing urgent coronary angiography and PCIs at our catheterization laboratory were enrolled in the study: 67 patients (34.5%) received the iso-osmolar contrast medium iodixanol (group A) and 127 patients (65.5%) received the hypo-osmolar contrast medium iopromid (group B). Results The overall incidence of CIN was 10.82%. Patients of group A showed a higher incidence of CIN than patients of group B (22.3 vs. 4.7%, P < 0.05). On univariate logistic analysis, age, pre-existing renal insufficiency, intra-aortic balloon pump (an indirect indicator of haemodynamic instability), dyslipidaemia, and postprocedural hypotension were risk indicators for the development of CIN after primary PCI. On multivariate logistic analysis, age and postprocedural hypotension remained significant independent correlates of CIN. Conclusions In emergency PCIs, CIN is a frequent complication mainly related to haemodynamic instability and pre-existing renal dysfunction. Since CIN is associated with a high in-hospital mortality rate, our data stress the need for the development and validation of new preventive strategies for renal protection during emergency PCIs.

d-Dimer increase after percutaneous transluminal angioplasty and clinical recurrence after primary revascularization in acute myocardial infarction? A pilot study

Abstract It has been reported that the increase of plasminogen activator inhibitor-1 activity immediately after elective coronary angioplasty is related to subsequent clinical recurrence in patients with chronic coronary artery disease. The aims of our study were to evaluate the behaviour of plasminogen activator inhibitor-1 and d-Dimer after revascularization in acute myocardial infarction patients treated with angioplasty and stenting and if this behavior is predictive of subsequent clinical recurrence. d-Dimer and plasminogen activator inhibitor-1 activity were evaluated in two groups of patients. Group 1 consisted of 54 consecutive patients undergoing primary angioplasty for acute myocardial infarction and Group 2 consisted of 48 patients undergoing elective angioplasty. Patients underwent control coronary angiography only in the case of clinical recurrence and/or positivity of provocative tests. d-Dimer and plasminogen activator inhibitor-1 baseline levels were significantly higher in group 1 than in group 2 (P<0.0005 and P<0.05, respectively). The percentage of group 1 patients with a post-procedural increase in d-Dimer was significantly higher among those with subsequent clinical recurrence with restenosis (61%) than among those with no recurrence (25%, P<0.05). No difference was observed in group 2. The percentage of group 2 patients in whom no decrease of plasminogen activator inhibitor-1 was observed after angioplasty was significantly higher (83%) among those with subsequent recurrence than among those with no recurrence (38%, P<0.05). This pattern was not observed in group 1. In conclusion, the role of early changes in plasminogen activator inhibitor-1 in predicting clinical recurrence after primary angioplasty in acute myocardial infarction patients is less clear than that observed after elective angioplasty. A significant role seems to be played by a more-marked clotting activation with increased fibrin formation.