First human experience with pulmonary vein isolation using a through-the-balloon circumferential ultrasound ablation system for recurrent atrial fibrillation.

BACKGROUND: Standard mapping and ablation of focal sources of atrial fibrillation are associated with very long procedure times and low efficacy. An anatomic approach to complete pulmonary vein isolation could overcome these limitations. METHODS AND RESULTS: Fifteen patients with atrial fibrillation refractory to medication underwent circumferential isolation of the pulmonary veins by using a novel catheter, with an ultrasound transducer (8-MHz) mounted near the tip, in a saline-filled balloon. Twelve atrial foci and/or atrial fibrillation triggers were identified in 9 patients (pulmonary vein locations: left upper, 3; right upper, 6; right middle, 1; right lower, 1; and left inferior, 1). In 5 patients, lesions were placed in the absence of any mapped triggers. Irrespective of trigger mapping, circumferential isolation of both upper pulmonary veins was attempted in all patients. The lower pulmonary veins were ablated when sinus rhythm activation mapping revealed evidence of a sleeve of atrial muscle in the vein. The median number of lesions per patient required to isolate 1 pulmonary vein was 4 (range, 1 to 29). After ablation, no evidence of narrowing was seen with repeat venography or follow-up computed tomography scan. After a mean follow-up of 35+/-6 weeks, 5 patients had recurrence of atrial fibrillation. Three responded to drugs that were previously ineffective, and 2 remained in atrial fibrillation. CONCLUSIONS: This novel ultrasound ablation system can successfully isolate multiple pulmonary veins. At early follow-up, this approach seems to be effective in preventing recurrent atrial fibrillation in a significant number of patients.

Determinants of arrhythmogenic ventricular activity detected on the body surface QRS in patients with coronary artery disease.

The prevalence of arrhythmogenic ventricular activity (AVA) was investigated in 166 patients with coronary artery disease. Thirty patients had documented ventricular tachycardia (VT)/ventricular fibrillation (VF). Bipolar X, Y, Z leads were signal-averaged and filtered with a 40-Hz, bidirectional, high-pass digital filter. The filtered QRS signals were analyzed for the amplitude of the last 40 and 50 ms; duration of low-amplitude potentials (less than 40 microV) in the terminal portion; and duration of the filtered QRS. A positive AVA test result was defined as the presence of 2 or more abnormal indexes. Of the 30 patients with VT/VF, 66% had positive AVA test results (AVA-positive patients). Of the 136 patients without VT/VF, 25% had positive AVA test results. The following univariate variables showed significant correlation with an AVA-positive test: age, previous myocardial infarction, previous VT/VF, left ventricular wall motion abnormalities and left ventricular ejection fraction. Multivariate stepwise discriminant function analysis revealed that the presence of previous myocardial infarction and history of sustained VT/VF were the only independent determinants of AVA. During electrophysiologic studies, sustained VT/VF could be induced in 77% of the AVA-positive patients (24 of 31) and in 30% of the AVA-negative patients (3 of 10). The survival probabilities for 6, 12 and 18 months of follow-up were 92%, 85% and 85% for the AVA-positive and 97%, 92% and 90% for the AVA-negative patients. Our findings support the concept that a positive AVA test result reflects areas of delayed ventricular activation. The areas of delayed ventricular activation are associated with previous myocardial injury and scar tissue and serve as an anatomic basis for reentry.(ABSTRACT TRUNCATED AT 250 WORDS)

Palliative coronary artery surgery in patients with severe noncardiac diseases.

Eight patients with severe systemic pathologies and refractory angina unsuitable for angioplasty were submitted to palliative surgical revascularization without the use of cardiopulmonary bypass and limited to the culprit vessels. Complete relief from angina was achieved in all patients without postoperative mortality and morbidity.

Pulsed Doppler echocardiographic analysis of mitral regurgitation after myocardial infarction.

In 72 patients with previous myocardial infarction (MI), mitral regurgitation (MR) was assessed by pulsed-wave Doppler echocardiography and compared with physical and 2-dimensional echocardiographic findings. MR was found by Doppler in 29 of 42 patients (62%) with anterior MI, 11 of 30 (37%) with inferior MI (p less than 0.01) and in none of 20 normal control subjects. MR was more frequent in patients who underwent Doppler study 3 months after MI than in those who underwent Doppler at discharge (anterior MI = 83% vs 50%, p less than 0.01; inferior MI = 47% vs 27%, p = not significant). Of 15 patients who underwent Doppler studies both times, 3 (all with anterior MI) had MR only on the second study. Of the patients with Doppler MR, 12 of 27 (44%) with a left ventricular (LV) ejection fraction (EF) greater than 30% and 1 of 13 (8%) with an EF of 30% or less (p less than 0.01) had an MR systolic murmur. Mitral prolapse or eversion and papillary muscle fibrosis were infrequent in MI patients, whether or not Doppler MR was present. The degree of Doppler MR correlated with EF (r = -0.61), LV systolic volume (r = 0.47), and systolic and diastolic mitral anulus circumference (r = 0.52 and 0.51, respectively). Doppler MR was present in 24 of 28 patients (86%) with an EF of 40% or less and in 16 of 44 (36%) with EF more than 40% (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of thrombolysis and atenolol or metoprolol on the signal-averaged electrocardiogram after acute myocardial infarction. Late Potentials Italian Study (LAPIS).

Late potentials (LPs) detected on the signal-averaged (SA) electrocardiogram (ECG) predict arrhythmic events after acute myocardial infarction (AMI). The effect of thrombolysis on the incidence of LPs after AMI is controversial and its impact on subsequent arrhythmic events is not known. Moreover, the effects of beta blockers on the SAECG have not been studied. Six hundred eighteen patients with AMI were studied; thrombolysis was given to 228 (37%). In comparison with patients treated conventionally, those receiving thrombolysis were significantly younger and more frequently male, had higher peak values of creatine kinase, a lower prevalence of non-Q-wave AMI, and a higher incidence of ventricular fibrillation in the acute phase, and more frequently received beta blockers. An SAECG obtained 6 to 8 days after AMI showed LPs in 24% of patients receiving and in 25% not receiving thrombolysis (p = NS). On admission, intravenous beta blockers were administered to 110 patients (18%); those receiving beta blockers were younger, had lower peak values of creatine kinase and more frequently received thrombolysis. LPs were less frequently found in patients treated than in those not treated with beta blockers (15 vs 27%; p = 0.007); however, this effect was found only in those with an ejection fraction > or = 40%. Independent predictors of LPs by multivariate analysis were an ejection fraction < 40% (p = 0.007), ventricular fibrillation in the acute phase (p = 0.02), and absence of beta-blocking therapy (p = 0.03). During a mean follow-up of 12 +/- 7 months, there were 39 cardiac deaths (6%), 13 of which were sudden (2%), and 9 sustained ventricular tachycardias.(ABSTRACT TRUNCATED AT 250 WORDS)

Ventricular arrhythmia induced by programmed ventricular stimulation after acute myocardial infarction.

The prevalence, characteristics and clinical significance of ventricular electrical instability with programmed ventricular stimulation was studied in 50 hemodynamically stable patients 17 to 40 days after acute myocardial infarction (AMI) using double extrastimuli at 2- and 10-mA intensity and from 2 right ventricular sites. Ventricular electrical instability was defined as induction of 10 or more consecutive intraventricular reentrant beats. Of 50 patients, 23 (46%) had ventricular electrical instability (10 of these had sustained ventricular tachycardia [VT] induced). No significant differences were observed between patients with and without ventricular electrical instability with respect to age, site of AMI, coronary prognostic index, maximal level of CK, number of narrowed coronary arteries and presence of severe wall motion abnormalities. During a mean follow-up of 11.2 months no patient died suddenly. During repeated Holter recordings patients with ventricular electrical instability had a higher incidence of nonsustained VT than did patients without ventricular electrical instability.

Electrophysiologic effects of somatostatin in man.

Experimental and clinical studies suggest that somatostatin, a regulatory peptide widely distributed in human tissues may have electrophysiologic effects. We studied a group of 14 patients who underwent a complete electrophysiologic study for different rhythm disturbances. Somatostatin significantly increased the spontaneous cycle length, the atrial and atrioventricular nodal effective refractory periods, and the Wenckebach cycle length. The AH and HV intervals during sinus rhythm remained unchanged. The effectiveness of somatostatin to interrupt paroxysmal supraventricular tachycardias was assessed in 18 patients. Termination was obtained in 15 (82.5%). Our results show that somatostatin has a significant electrophysiologic effect on the human heart, and confirm its clinical effectiveness in some arrhythmias.

Conventional left atrial versus superior septal approach for mitral valve replacement.

BACKGROUND: This study was designed to evaluate the safety and effectiveness of the superior septal approach for routine mitral valve replacement. METHODS: One hundred forty-six consecutive patients undergoing mitral valve replacement at our institution were randomly assigned to undergo the procedure using either the conventional left atriotomy or the superior septal approach. Postoperatively and during the follow-up, 12-lead electrocardiography, 24-hour Holter monitoring, and transthoracic and transesophageal echocardiography were performed in all patients. RESULTS: The cardiopulmonary bypass and cross-clamp times were significantly higher in the superior septal group. No significant difference in blood loss was found between the two groups, and no residual atrial septal defect was found in patients in whom we used the superior septal approach. The maintainance of sinus rhythm at late follow-up and the incidences of postoperative arrhythmias and newly developed atrioventricular block were not significantly different between the two groups. CONCLUSIONS: The use of the superior septal approach to the mitral valve is not associated with a greater incidence of rhythm disturbances or other complications. Because this approach provides optimal exposure of the valve and the subvalvular apparatus, it has been routinely adopted for use in patients undergoing mitral valve replacement at our institution.

Tall right precordial R waves in members of a family with hypertrophic cardiomyopathy.

We recently observed a family with tall R waves from V1 to V3 in different relatives, regardless of the actual presence and localization of idiopathic left ventricular hypertrophy.

Effects of subcutaneous recombinant human erythropoietin in patients on continuous ambulatory peritoneal dialysis.

The use of recombinant human erythropoietin (rHuEPO) has revolutionized the treatment of renal anemia, but the dose regimens, the optimal frequency, and the effects on other target organs like the central nervous systems (CNS) are still under discussion. We designed a prospective, ongoing study with 10 stable continuous ambulatory peritoneal dialysis (CAPD) patients (6 males, 4 females; mean age 64.4 +/- 7.8 years), with a pretreatment hemoglobin (Hb) < 7.0 g% and requiring regular blood transfusions. Seven patients were treated with 4000 U rHuEPO once weekly (Eritrogen, Boehringer Mannheim), 2 patients received 4000 U every 5 and 8 days, and the last one 4000 U every 10 days. The target hematocrit was 33% and Hb 10.0 g%. The CNS activity was recorded as visual (VEP), brainstem (BAER), and somatosensory (SEP)-evoked potentials. The mean Hb concentration increased from 6.9 +/- 1.2 g% to 10.3 +/- 1.6 g% (p < 0.001) over 8 weeks. There were no significant changes in urea, creatinine, and potassium levels, and urine output. rHuEPO induced a decrease in latency of P100 VEP, in the four main components of BAER, and in the P27-N35 intertime of SEP. Parallel to the improvement of red cell indices, patients experienced a dramatic improvement in well-being. The subcutaneous administration of a single vial of rHuEPO is safe, convenient, and inexpensive in CAPD. The role of rHuEPO treatment in improving the electrophysiological brain function in uremic and anemic patients remains to be studied and may not necessarily be based on improved cerebral oxygenation.

Valve replacement with the tilting disc Sorin prosthesis in patients with narrow aortic annulus.

The Authors summarize their 5-year experience of the clinical use of the Sorin tilting disc prosthesis in 40 patients (group A) with narrow aortic annulus, compared with a control group (group B: 116 patients) where a larger Sorin prosthesis was implanted. Follow-up lasted from 1 to 60 months, with a mean of 25.6 +/- 12.3 in group A and 20.4 +/- 11.9 in group B. Early and late mortality were low: 1/40 and 2/39 (2.5 and 5.1%) in group A and 4/116 and 9/112 (3.4 and 8.0%) in group B (p = NS): only two deaths, one in each group, were prosthesis-related. Actuarial survival was comparable: 91.2% (CL: 96.3-86.1%) in group A and 78.0% (CL: 87.6-68.4%) in group B, as were probability of being event-free and alive, non-reoperated and with few or no symptoms [group A: 61.7% (CL: 72.4-51.0%) and 77.4% (CL: 85.9-68.9%) respectively; group B: 78.8% (CL: 83.4-74.2%) and 61.1% (CL: 85.9-68.9%) respectively]. The Authors conclude that the Sorin tilting disc prosthesis is a reliable valve substitute in the narrow aortic annulus; they recommend that enlargement procedures should be confined only to patients with annulus size less than 19 mm.

Severe involvement of the conduction system in a patient with sclerodermal heart disease. An electrophysiological study.

A case of progressive systemic sclerosis with syncopal symptoms is reported. The presenting ECG pattern was that of an anterior myocardial infarction. The clinical history and the coronary angiography excluded significant coronary atherosclerotic heart disease. The ECG pattern evolved from the infarctual pattern associated with right bundle branch block to probably major degree of right bundle branch block associated with left posterior fascicular block. M-mode echocardiography, heart catheterization and angiographic studies did not reveal significant mechanical impairment of the left or right ventricle function. His bundle electrogram documented a markedly prolonged H-V interval, confirming an advanced impairment of distal conducting system. This case supports the suggestion that intraventricular conduction disorders in sclerodermal heart disease are not always related to diffuse myocardial involvement. The risk of sudden death justifies accurate electrophysiological evaluation in selected patients with sclerodermal cardiopathy.

[Mitral valve substitution, using the Lillehei-Kaster prosthesis]. / La sostituzione valvolare mitralica con la protesi di Lillehei-Kaster.

Personal experience acquired in the course of 177 mitral valve replacements with a Lillehei-Kaster prosthesis up to June 1977 is discussed. Intraoperative mortality was 8.5%. Postoperative mortality (as at 31-12-1976) was 5.3%. The clinical, radiological, and ergometric findings were fully satisfactory. Haemodynamic examination at rest and during effort revealed improved pressure and heart capacity values. The mean transprosthetic gradient at rest was 5.61 and rose to 13.53 (after uncalibrated effort). Thromboembolism was noted in 5 patients (3.1%), as in the literature. The haemodynamic features and low thrombogenicity of the Lillehei-Kaster prosthesis would thus appear to make it a sound replacement for the mitral valve.

[What is the best treatment in massive pulmonary embolism: anticoagulants, thrombolytics or surgical embolectomy?]. / Quale trattamento per l'embolia polmonare massiva: gli anticoagulanti, i trombolitici o l'embolectomia chirurgica?

The aim of this work was to identify the best treatment available for massive pulmonary thromboembolism which still remains a frequent and sometimes lethal complication for surgical and non-surgical patients. The Authors underline the difficulties of diagnosis and the need for therapy at the earliest possible stage. At present, clinical management involves the use of: anticoagulants, thrombolytic agents and surgical embolectomy. In conclusion, the authors state that pulmonary thromboembolism, even when massive, has been transformed into a medically interesting pathology which can be cured using heparin and thrombolytic agents. However, surgical treatment is mandatory when patients reveal adverse effects to drug therapy, when medical therapy is insuccessful, or when patients are seriously ill with recurrent cardiac arrest.

[Aortic valve replacement in a case of Takayasu's disease with polydistributed localization]. / Sostituzione valvolare aortica in un caso di malattia di Takayasu a localizzazione polidistrettuale.

We report a case of a 49 year-old woman suffering from severe aortic regurgitation due to Takayasu's disease involving the ascending and abdominal aorta and the brachial arteries. The patient was managed successfully with aortic valve replacement. Considering the Literature data, the pathogenesis of the aortic insufficiency and the main surgical and anaesthesiologic problems related to the Takayasu's disease are discussed.

[Blood platelet count and bubble oxygenators. Changes induced by the oral administration of dipyridamole]. / Piastrinemia e ossigenatori a bolle. Varianti indotte dalla somministrazione di dipiridamolo per os.

The changes in thrombocythemia in patients subjected to extracorporeal circulation (ECC) and pretreated with dipyridamole per os have been examined and compared with a control group in whom the drug was not used; in all patients a circuit with bubble oxygenator was employed. Measurements were carried out before sternotomy, 10' and 60' after ECG, 1 h after the start of intensive therapy and on the 1st surgical day. The variations in thrombocythemia were assessed in consideration of the thrombocythemia/Ht ratio, so as to eliminate the dilution variable. On the basis of the results obtained, it is considered that preoperative treatment with dipyridamole is effective in limiting the fall in thrombocythemia during ECC. The effect of the drug is prevalent in the initial stage of ECC, probably reducing platelet aggregation to non-biological surfaces of the circuit.

[Reversibility of left ventricular functional damage after valve replacement in patients with chronic aortic valve insufficiency]. / Reversibilità del danno funzionale del ventricolo sinistro dopo sostituzione valvolare in pazienti affetti da insufficienza valvolare aortica cronica.

The authors study retrospectively some preoperative echocardiographic findings and their importance as predictors of reversible myocardial dysfunction. The functional status of 57 survivors after isolated aortic valve replacement was evaluated with exercise testing and on this ground the patients, were divided into three groups: A (28 pts) greater than 60%; C (10 pts) less than 40%; B (19 pts) from 40% to 60%. The authors conclude that the postoperative improvement in functional status is strictly correlated with some preoperative echocardiographic indexes (end-diastolic dimension, end-systolic dimension, shortening fraction, mean end-systolic radius/thickness ratio, end-systolic wall stress, myocardial mass, ejection fraction) with are also predictive of operative mortality. The authors consider the principal values of beginning left ventricular impairment: a) end-systolic dimension greater than or equal to 5.5 cm; b) shortening fraction less than 27%; c) mean end-systolic radius/thickness ratio greater than 2.5; d) end-systolic wall stress greater than 240 mmHg.

[Classification of congenital aortic stenosis]. / Classificazione delle stenosi aortiche congenite

Recent epidemiological data relating congenital stenosis of the aorta are cited. An anatomical criterion is used in the formation of three classification groups, each containing a number of different types. There are no clear-cut clinical pictures corresponding to these anatomical varieties, however, so that differential diagnosis is dependent on the haemodynamic and contrastographic data. There are, on the other hand, clinical signs that serve as pointers to the site of the stenosis.

[Major complications of median sternotomy]. / Le complicanze maggiori della sternotomia mediana.

After examining the modalities of sternal perfusion and the techniques of median sternotomy, with special regard to closure techniques, personal experience of 1000 sternotomies is reviewed. Complications may be major or minor, incidence was 1,8% and total mortality two cases. After reviewing the various causes of sternal dehiscence, reported and personal experience of the various techniques for preventing and treating the complication is discussed.

[Infectious endocarditis. Role of surgical therapy]. / Considerazioni sull'endocardite infettiva. Ruolo della terapia chirurgica.

The problem of infectious endocarditis (IE) is approached through a review of personal experience. The series examined consists of patients, 17 with active and 21 dormant infection. Furthermore 12 in the first group, 18 in the second had natural heart valves, while 5 in group I, 3 in group II had been given artificial ones. After an analysis of the aetiopathogenic, clinical and diagnostic aspects of the condition with emphasis on the fact that Staphylococcus aureus is currently more responsible for infections in natural valves and the epidermidis for acute prosthesis infections which have a higher early and late mortality rate (40% in hospital, 33.3% long-term), the paper discusses the criteria for surgical intervention. In line with opinions expressed in the literature, it is pointed out that, while the patient's haemodynamic status is certainly the main criterion for any decision, other factors such as embolism, impaired conduction, kidney failure and expansion of the infection to contiguous tissues, should not be under-estimated.