Prognostic value of high dose dipyridamole echocardiography in patients with chronic coronary artery disease and preserved left ventricular function.

OBJECTIVES: The prognostic value of dipyridamole echocardiography was assessed in patients with chronic coronary artery disease and preserved left ventricular function. BACKGROUND: Few data are available on the prognostic value of dipyridamole echocardiography in patients with a low risk of cardiac events. METHODS: Two hundred sixty-eight consecutive patients with stable, proven or suspected coronary artery disease and ejection fraction > or = 0.40 underwent high dose (up to 0.84 mg/kg body weight) dipyridamole echocardiography. In 204 patients definite exercise electrocardiographic (ECG) results were also available. RESULTS: During a mean (+/- SD) follow-up period of 16 +/- 8 months (range 6 to 36), 33 spontaneous events occurred: 15 "hard" events (cardiac death [n = 6], myocardial infarction [n = 9]) and 18 "soft" events (unstable angina). Events occurred more frequently in patients with positive findings on dipyridamole echocardiography (59% vs. 3%, p < 0.001; hard events 24% vs. 2%, p < 0.01). A positive response at the low dose (up to 0.56 mg/kg) identified patients with a high incidence of hard events (7 of 16 patients, sensitivity 50%, specificity 96%). In patients with an exercise ECG, a comparable sensitivity for cardiac events was found (89% vs. 93%, p = NS), but dipyridamole echocardiography was more specific (91% vs. 61%, p < 0.01). A positive response on the low work load exercise ECG (< 8 min) and a positive response to low dose dipyridamole echocardiography had similar accuracy (82% vs. 90%, p = NS). Cox analysis identified dipyridamole echocardiography as the best predictor of cardiac events (odds ratio [OR] 20.9, 95% confidence interval [CI] 10.8 to 37.9); the highest risk of hard events was found in patients with a positive response to low dose dipyridamole echocardiography (OR 25.4, 95% CI 12.2 to 54.1). CONCLUSIONS: In patients with chronic coronary artery disease and a low incidence of cardiac events, dipyridamole echocardiography was effective in prognostic stratification, and positive low work load exercise ECG results were a reliable predictor of subsequent events. Consequently, dipyridamole echocardiography should be considered a complementary tool in the presence of high work load positivity or ambiguous exercise ECG results.

Role of telecardiology in the assessment of angina in patients with recent acute coronary syndrome.

We compared two models of assistance (telecardiology versus usual care) for patients discharged after acute coronary syndrome (ACS), in the assessment of angina. Two hundred patients were randomized into two groups at discharge for ACS: Group A to telecardiology and Group B to usual care. Early hospital readmission (in the first month) occurred in 16 patients (seven in Group A and nine in Group B). Six of Group A were readmitted for a cardiac cause (non-cardiac in one). Angina was the only cardiac cause. Five of the Group B patients were readmitted for a cardiac cause (non-cardiac in four). The results of the present study emphasize that patients with ACS suffer from a definite rate of cardiac symptoms within the first month (63%). Angina occurs more frequently within the first two weeks (68% of cases). Telecardiology slightly reduces hospital readmissions (telecardiology 44% versus usual care 56%), but better identifies true angina.

[Late ventricular potentials and acute myocardial infarction]. / Potenziali tardivi ventricolari (PT) ed infarto miocardico acuto (IMA).

BACKGROUND: The presence of late ventricular potentials was evaluated in a group of patients following acute myocardial infarction hospitalised in our division. MATERIALS AND METHODS: Recordings were made between the 10th and 12th day of the pathology. The criteria for positivity were the presence of three parameters: QRSD > or = 114 msec, LAS 40 > or = 38 msec, RMS 40 < or = 20 mv. These were present in 21 patients (18 males and 3 females). Inferior acute myocardial infarction (AMI) was found to be present in 15 cases, anterior AMI in 4 cases and AMI with an unspecified localisation in 2 cases. The mean duration of qrsd was 122 msec, the mean duration of low amplitude potentials (LAS 40) were 53.5 msec, the mean amplitude of the last 40 msec (RMS 40 was 8.9 mv). CONCLUSIONS: In conclusion, the authors affirm that late potentials were present in the majority of patients with inferior AMI and the search for the latter represents an important stage in the post-AMI prognostic stratification. Delta is the positive correlation between late potentials and ventricular tachycardia in postinfarction. This non-invasive test is comparable to electrophysiological induction tests in terms of predictive capacity of arrhythmic event and/or sudden death.

[Heart arrest]. / L'arresto cardiaco.

Cardiac arrest is one of the leading causes of mortality in industrialized countries and is mainly due to ischemic heart disease. According to ISTAT estimates, approximately 45,000 sudden deaths occur annually in Italy whereas according to the World Health Organization, its incidence is 1 per 1000 persons. The most common cause of cardiac arrest is ventricular fibrillation due to an acute ischemic episode. During acute ischemia the onset of a ventricular tachyarrhythmia is sudden, unpredictable and often irreversible and lethal. Each minute that passes, the probability that the patient survives decreases by 10%. For this reason, the first 10 min are considered to be priceless for an efficacious first aid. The possibility of survival depends on the presence of witnesses, on the heart rhythm and on the resolution of the arrhythmia. In the majority of cases, the latter is possible by means of electrical defibrillation followed by the reestablishment of systolic function. An increase in equipment alone does not suffice for efficacious handling of cardiac arrest occurring outside the hospital premises. Above all, an adequate intervention strategy is required. Ambulance personnel must be well trained and capable of intervening rapidly, possibly within the first 5 min. The key to success lies in the diffusion and proper use of defibrillators. The availability of new generation instruments, the external automatic defibrillators, encourages their widespread use. On the territory, these emergencies are the responsibility of the 118 organization based, according to the characteristics specific to each country, on the regulated coordination between the operative command, the crews and the first-aid means. Strategies for the handling of these emergencies within hospitals have been proposed by the Conference of Bethesda and tend to guarantee an efficacious resuscitation with a maximum latency of 2 min between cardiac arrest and the first electric shock. The diffusion of external automatic defibrillators is a preventive measure. Such equipment has permitted early defibrillation by non-medical first-aid personnel. These instruments contain software capable of recognizing an arrhythmia which may be defibrillated and of instructing the operator whether and when to press the defibrillation button. The latest instruments deliver the shock by means of a biphasic wave necessitating a lesser amount of energy which can be provided by lighter condensers. Thus such equipment weighs just a couple of kilograms. As suggested by ILCOR, for reasons of priority, such instruments should not only be available within hospitals and in ambulances but also on the territory, in particular in more crowded places. The availability of external automatic defibrillators in such places should reduce the time latency before intervention and thus increase survival. The ILCOR guidelines have suggested the constitution of an itinerary team well equipped for defibrillation and composed of trained personnel of State Institutions such as the Municipal Police, Traffic Police and the Fire Brigades. With regard to the majority of arrhythmias amenable to defibrillation which occur at home or in less crowded places, other strategies, such as primary prevention and training programs for categories at increased risk, must be employed. Antiarrhythmic drugs have long been considered the best solution for the prevention and treatment of ventricular tachyarrhythmias. However, the approach to these pathologies has drastically changed during the last few years owing to accumulating evidence in favor of defibrillators which may be implanted for the primary and secondary prevention of malignant ventricular arrhythmias. For patients with previous cardiac arrest, randomized studies have proven the advantages of such an approach compared to medical therapy. On the basis of the above, the guidelines for the use of antiarrhythmic implants have been modified. In most western countries, the laws regarding this aspect of medicine have recently been renewed. In the United States, where there is the "Law of the Good Samaritan", in order to protect and acquit persons who give first-aid, many states have adopted new laws which promote the use of external automatic defibrillators. Following recent dispositions by the President of the United States that defibrillators should be present in all Federal properties and on civil aircraft, a new Federal Law is about to pass. Italy lacks legislation regarding the use of defibrillators: in order to rectify this position, which is still anchored to existing dispositions of the civil and penal codes including those regarding the omission of first-aid, a bill entitled "The definition and modalities of the use of the external cardiac defibrillator" has recently been presented.

[The effect of cardiovascular rehabilitation on the variability of the RR cycle after a first uncomplicated acute myocardial infarct]. / Effetto della riabilitazione cardiovascolare sulla variabilità del ciclo RR dopo un primo infarto miocardico acuto non complicato.

BACKGROUND: The aim of this study was to verify the changes in the autonomic balance by means of heart rate variability assessment in patients with myocardial infarction referred for cardiac rehabilitation. METHODS: We studied 122 patients (79 males, 43 females, mean age 56 +/- 5 years), with a first uncomplicated myocardial infarction (anterior 48, thrombolysis 72), Killip class 1, preserved left ventricular function (ejection fraction 49 +/- 6%). All patients were free of inducible residual ischemia. Four weeks after myocardial infarction, patients were randomized into two groups; Group 1 (n = 58) referred for an 8 week cardiac rehabilitation program (scheduled: 24 sessions); Group 2 (n = 64): normal daily physical activity. During a 24-hour Holter ECG monitoring the following parameters were calculated in pharmacological wash-out at randomization (T0) and at the end of cardiac rehabilitation/control period (T1): mean value of RR intervals (RR), its standard deviation (SDNN), pNN50, rMSSD in the time domain; low frequency (LF) and high frequency (HF) value and the LF/HF ratio in the frequency domain. T1-T0 changes in percent values (delta %) were considered and compared between the two groups. RESULTS: Thirty-one patients were excluded from the study either for insufficient adhesion to the cardiac rehabilitation program (< 13 sessions, 22 patients) or recurrent ischemia (3 Group 1 patients and 3 Group 2 patients) and non-assessable 24-hour Holter ECG monitoring (3 patients). Thirty-one Group 1 patients and 60 Group 2 patients completed the study with a first and a second 24-hour Holter ECG monitoring performed at 30 +/- 3 days and 60 +/- 4 days respectively. At the same time an ergospirometric test was performed to evaluate cardiopulmonary function by means of exercise time, maximum oxygen consumption, anaerobic threshold, exercise time at the anaerobic threshold, and maximum oxygen consumption at the anaerobic threshold. Twenty-eight Group 1 patients and 44 Group 2 patients completed the study with a first and a second ergospirometric test. Baseline heart rate variability parameters were comparable in the two groups. During the observation period only in Group 1 patients heart rate variability parameters changed significantly: RR (Group 1 = +18.3 +/- 21.3; Group 2 = +4.2 +/- 5.2, p = 0.000), pNN50 (Group 1 = 45.0 +/- 38.9; Group 2 = +24.2 +/- 34.7, p = 0.011), HF (Group 1 = +81.6 +/- 124; Group 2 = -28.7 +/- 75.4, p = 0.014) and LF/HF ratio (Group 1 = -26.0 +/- 16.1; Group 2 = -4.9 +/- 6.1, p = 0.062). There were no significant differences in SDNN, rMSSD and LF. A linear correlation between delta LF/HF ratio and baseline LF/HF ratio values was found in Group 1 (r = 0.489, p = 0.006), whereas no correlation was found between this parameter and age, ejection fraction, creatine phosphokinase, and infarct localization. Group 1 patients had a significant improvement in exercise tolerance compared to Group 2 patients. CONCLUSIONS: A cardiac rehabilitation program positively modifies the sympatho-vagal balance in patients with uncomplicated myocardial infarction, increasing the parasympathetic tone and exercise tolerance.

[Management of ventricular arrhythmia in chronic congestive heart failure]. / La terapia delle aritmie ventricolari nello scompenso cardiaco cronico.

PURPOSE: To evaluate efficacy and indications of therapy for ventricular arrhythmias in patients with chronic congestive heart failure. DESIGN: A review of most significant and recent clinical trials was performed. RESULTS: In patients with severe left ventricular dysfunction, the desirable actions of antiarrhythmic drugs are attenuated and their negative inotropic and proarrhythmic actions are enhanced. Treatment should be limited to patients with malignant ventricular arrhythmias, or to patients considered at high risk. When indicated, amiodarone is usually well tolerated and safe. The prevention of sudden death in patients with heart failure should be based on optimized therapy of pump failure, reducing left ventricle work load and modulating neurohormonal systems with ACE-inhibitors and betablockers drugs. Further, an important role is held by anti-ischemic therapy, revascularization procedures, anticoagulant therapy and prevention of electrolytes unbalances. Patients with sustained of high risk arrhythmias, resuscitated from a cardiac arrest, should be considered for transvenous Implantable Cardioverter Defibrillator (ICD) implant. CONCLUSIONS: Ventricular arrhythmias are common in heart failure patients, represent an important cause of sudden death and the choice of treatment is difficult because of the complexity of underlying mechanisms, frequency of adverse reactions and the severity of left ventricular dysfunction.

[Effect of the acute administration of molsidomine in refractory congestive heart failure. A double-blind randomized non-invasive study]. / Effetto della somministrazione acuta di molsidomina nello scompenso cardiaco congestizio refrattario. Studio non invasivo randomizzato in doppio cieco.

The effect of vasodilator Molsidomine (M) vs placebo on left ventricular dimensions and function measured by echocardiography was evaluated in a randomized study on 23 patients (pts) with refractory congestive heart failure (R CF) (NYHA class III-IV). The pts were randomized in two groups: group A (12 pts) received M, group B received an identical appearing placebo. Adequate echocardiograms were obtained before and one hour after 2 tablets of M (4 mg) or P; left ventricular end-diastolic and end-systolic diameters (LVEDD and LVESD), mean rate of circumferential shortening and left ventricular fractional shortening were calculated on the echocardiograms obtained. At the same time mean arterial pressure (MAP) and heart rate were measured. In group A, the single-dose test induced a significant reduction in LVEDD (74.1 +/- 7.2 to 72.1 +/- 7.1 mm; p less than 0.01), in LVESD (64.4 +/- 8.4 to 61.6 +/- 7.4 mm; p less than 0.01) and in MAP (96.5 +/- 8.3 to 85.4 +/- 7.2 mmHg; p less than 0.05). No significant changes were noted in the other parameters. Moreover, changes of parameters evaluated in group A between pts with idiopathic cardiomyopathy and pts with ischemic heart disease showed no statistical differences. Thus, acute Molsidomine therapy is effective in reducing left ventricular diameters and MAP in pts with RCF without changes of echocardiographic contractility indexes.

[Comparison of anti-arrhythmic therapy guided by the transesophageal electropharmacologic test and emperic therapy in the prophylaxis of atrial fibrillation recurrence]. / Confronto tra la terapia antiaritmica guidata dal test elettrofarmacologico transesofageo e la terapia empirica nella profilassi delle recidive di fibrillazione atriale.

BACKGROUND: There is no written data about the efficacy of transesophageal electropharmacologic test (TEPT) to guide antiarrhythmic therapy in the prophylaxis of paroxysmal atrial fibrillation (PAF) recurrences. Aim of this study was to assess the efficacy of TEPT compared to empiric treatment in the prophylaxis of PAF. METHODS: One-hundred-sixty patients (pts) with previous episodes of PAF were randomized in two groups: Gr A (90 pts) was submitted to basal transesophageal electrophysiologic study (BTES); Gr B (70 pts) was submitted to randomized empiric antiarrhythmic therapy with flecainide (F), propafenone (P) and sotalol (S). The end-points of stimulation protocol in Gr A were the induction of sustained atrial fibrillation (SAF)- > or = 1 min duration- or the end of protocol. SAF was inducible in 68/90 pts (Gr A1) while it was not in 22/90 pts (Gr A2). Pts in Gr A1 were subsequently submitted to TEPT at steady-state of F, P or S randomized in first choice. Pts responders (R) (SAF non inducible) were submitted to TEPT with other antiarrhythmic drugs randomized in second choice: R were followed-up with the same drug in chronic oral assumption, while non responders (NR) were submitted to TEPT with the last drug and followed-up with the same drug both in R and NR case. The same stimulation protocol was employed in TEPT as in BTES. Pts in Gr A2 withdrew from the study. During follow-up all-pts were submitted to periodic specialist examinations every three months. In case of PAF recurrence pts withdrew from the study. RESULTS: Mean follow-up duration in the study population was 17.5 +/- 8.5 months. One-hundred-eight TEPT were performed in Gr A1: 36 tests with F, 40 with P and 32 with S. Twenty pts were R with F (55% of tests) and 17 finished the follow-up, 22 pts were R with P (55% of tests) and 16 finished the follow-up, 19 pts were R with S (59% of tests) and 15 finished the follow-up; 3 pts with F, 2 pts with P and 2 pts with S were NR in last choice and finished the follow-up. In Gr A1 61/68 pts (90%) were R and 55/68 (81%) finished the follow-up (13 pts withdrew from the study). In Gr B (70 pts) 23 pts were randomized to F and 20 finished the follow-up, 24 pts were randomized to P and 20 finished the follow-up, 23 pts were randomized to S and 20 finished the follow-up (10 pts withdrew from the study). PAF recurrences during follow-up in Gr A1 were in 15/55 pts (27%): 9/48 pts (19%) R and 6/7 pts (86%) NR, and in Gr B in 41/60 pts (68%). Gr A1 vs Gr B p < 0.001. Univariate and multivariate statistical analysis showed the empiric treatment as the only variable with high predictive value for PAF recurrences (risk ratio 1.53). PPV and NPV of TEPT were respectively 86 and 81%. CONCLUSIONS: TEPT-guided antiarrhythmic therapy in the prophylaxis of PAF recurrences seems to be an effective method in predicting the efficacy of the chronic antiarrhythmic therapy, when compared to the empiric treatment. The non inducibility of SAF at TEPT would have a high predictive value for event-free follow-up.

[A comparison between flecainide and sotalol in the prevention of recurrences of paroxysmal atrial fibrillation]. / Confronto tra flecainide e sotalolo nella profilassi delle recidive di fibrillazione atriale parossistica.

OBJECTIVES: Aim of the present study was to assess the efficacy and safety of flecainide (F) and sotalol (S) for the prevention of recurrences of paroxysmal atrial fibrillation (PAF). METHODS: Sixty-six patients with PAF (> or = 3 episodes of atrial fibrillation in the last year) in sinus rhythm, were randomized to pharmacological oral treatment with F (20 patients-Group A), with S (20 patients-Group B) and placebo (P) (26 patients-Group C). During the follow-up (one year duration) were evaluated on I, III, VI and XII months the number and tolerance of the atrial fibrillation recurrences, cardiac and/or noncardiac side effects. The patients with more than two recurrences in the same follow-up interval withdrew from the study. In each patient 14 clinical and laboratory variables were evaluated. RESULTS: After 12 months were arrhythmia-free respectively 70% of Group A patients, 60% of Group B patients, 27% of Group C patients. Univariate analysis showed that treatment with F was related to decrease of atrial fibrillation recurrences (one recurrence 67%, two recurrences 81%, three recurrences 81%), treatment with S was related to decrease of recurrences (two recurrences 59%); the variable most significantly related to the risk of arrhythmia recurrence is the higher value of basal cardiac rate (one recurrence t = 2.15, two t = 2.22, three t = 2.96, four t = 2.06). There was not statistically significant difference in maintenance of sinus rhythm at the end of the follow-up between the groups of patients on F and S (p = 0.163); treatment efficacy was significantly higher than P (p = 0.002). Multivariate analysis showed that treatment with F and S decreases the risk of arrhythmia recurrence respectively of 85% and 76% versus placebo at the end of the follow-up. The incidence of cardiac and/or noncardiac side effects was not clinically significant. CONCLUSION: F and S are both effective and safe for prevention of PAF, with 70% and 60% respectively of patients arrhythmia-free after 12 months of treatment. Side effects were common, but clinically significant adverse events were uncommon. A higher value of basal cardiac rate was predictive of atrial fibrillation recurrences in the patients during treatment.

Multicenter trial on prognostic value of inducible ischemia, assessed by dobutamine stress echocardiography and exercise electrocardiography test, in patients with uncomplicated myocardial infarction, treated with thrombolytic therapy.

BACKGROUND: Thrombolysis has reduced early and longterm mortality by about 20%; sometimes, however, there is a re-occlusion of the infarct related artery or an unsuccessful thrombolysis. In these situations, there is a possible increase in detrimental events in the follow-up. OBJECTIVES: The aim of the study was to compare the prognostic value of dobutamine echocardiography (DET) and ECG exercise test (EET) in pts submitted to thrombolysis. METHODS: One hundred and fifty-one pts, with acute uncomplicated myocardial infarction, were enrolled. The pts were able to perform EET and had a sufficient echocardiographic window; 58 had anterior myocardial infarction (38%), 79 had inferior (52%), 2 had lateral (1%), 12 had non-Q (8%). EET was performed with an initial load of 25 Watt, and thereafter, 25 W every two minutes. DET was performed with step-wise infusion every three minutes (5, 10, 20, 30 and 40 mcg/kg/min.). If the target heart rate was not reached, a further dose of 40 mcg/kg/min. together with atropine 0.25-1 mg was administered, in the absence of signs and symptoms of ischemia. RESULTS: During a mean (+/- SD) follow-up period of 8 +/- 4.5 months (range 1-23), 16 spontaneous events happened (4 deaths, 5 non-fatal re-infarctions, 7 unstable angina). One-hundred and three EET (68%) were negative for ongoing ischaemia, while 48 were positive, 79 DET (52%) were negative for ongoing ischaemia and 72 were positive (48%). Statistical results: DET and EET had a sensitivity of 41% and 54%, a specificity of 57% and 74%, a positive predictive value of 7% and 14%, a negative predictive value of 91% and 95%, an accuracy of 56% and 73%. Kaplan-Maier survival curves demonstrated that patients with Peak Wall motion > 1.8 and EET score > 3, had the higher risk of spontaneous events. CONCLUSION: A few spontaneous events happened in the follow-up. These data demonstrate that patients treated with thrombolysis are not at high risk of spontaneous events. DET and EET, therefore, have had a high negative predictive value. For this reason, we can conclude that pts with negative tests can be considered at low risk and do not need any further investigations.