Frontiers of robotic endoscopic capsules: a review

Digestive diseases are a major burden for society and healthcare systems, and with an aging population, the importance of their effective management will become critical. Healthcare systems worldwide already struggle to insure quality and affordability of healthcare delivery and this will be a significant challenge in the midterm future. Wireless capsule endoscopy (WCE), introduced in 2000 by Given Imaging Ltd., is an example of disruptive technology and represents an attractive alternative to traditional diagnostic techniques. WCE overcomes conventional endoscopy enabling inspection of the digestive system without discomfort or the need for sedation. Thus, it has the advantage of encouraging patients to undergo gastrointestinal (GI) tract examinations and of facilitating mass screening programmes. With the integration of further capabilities based on microrobotics, e.g. active locomotion and embedded therapeutic modules, WCE could become the key-technology for GI diagnosis and treatment. This review presents a research update on WCE and describes the state-of-the-art of current endoscopic devices with a focus on research-oriented robotic capsule endoscopes enabled by microsystem technologies. The article also presents a visionary perspective on WCE potential for screening, diagnostic and therapeutic endoscopic procedures.

An electromyographic study of the vastii muscles during open and closed kinetic chain submaximal isometric exercises

BACKGROUND

Rehabilitation programs for patients with patellofemoral dysfunction aim to recruit the vastus medialis obliquus muscle (VMO) in an attempt to reduce pain and to improve patellar tracking.

OBJECTIVES

The aim of the present study was to use surface EMG to assess the effectiveness of two isometric submaximal contractions (10% and 60% of maximal voluntary contraction, MVC) in promoting preferential activation of VMO over vastus medialis longus (VML) and vastus lateralis (VL) in open and closed kinetic chain isometric exercises with the knee joint fixed at 30, 60 and 90 degrees of flexion.

METHODS AND MEASURES

Surface electromyography (EMG) signals were recorded with linear adhesive arrays of four electrodes from fourteen healthy young men (age 23.5±3.2, mean±SD) during isometric knee extension contractions at 10% and 60% of the maximum voluntary contraction (MVC) for 1 min and 20 s respectively at 30, 60 and 90 degrees of knee flexion. Initial values and rate of change (slope) of mean frequency (MNF), average rectified value (ARV) and conduction velocity (CV) of the EMG signal were calculated.

RESULTS

Comparisons between the force levels produced at 10% and 60% MVC revealed that the initial values of ARV and CV for the VL, VML and VMO muscle were greater at 60% MVC compared to 10% MVC (3-way ANOVA; F=536; p<0.001, F=49: p<0.01 for ARV and CV respectively). Comparisons between the different muscles demonstrated lower initial values of CV for VMO compared to VL and VLM at 10% and 60% of MVC (F=15; p<0.05). In addition, initial estimates of ARV were higher for VMO compared to VML at both force levels (F=66; p<0.05). Comparisons between open and closed kinetic chain exercises revealed higher initial estimates of ARV for open kinetic chain knee extension at both force levels (F=62; p<0.01). In addition, the absolute value of MNF slope appeared to increase at higher angles for closed kinetic chain at 60% MVC while it was minimum at 60° degrees for open kinetic chain. No significant differences were observed in the rate of change of CV and MNF among the three muscles.

CONCLUSIONS

Based on the results of this study, both open and closed kinetic chain exercise similarly activate the three portions of the quadriceps muscle, suggesting that selective training of the vastii muscle is not achievable in these conditions.

Pharmacological treatment of atrial fibrillation: a review on prevention of recurrences and control of ventricular response

Atrial fibrillation is the most common sustained arrhythmia, however its treatment remains controversial and problematic. Electrical or pharmacological cardioversion are able to restore sinus rhythm in many patients but maintenance of sinus rhythm requires long term treatment with antiarrrhythmic agents. Today there is major concern regarding the ventricular proarrhythmic effects of antiarrhythmic drugs because they may increase mortality. Even non-cardiac toxicity of these agents must be considered. An alternative strategy based on pharmacological control of ventricular response rate coupled with antithromboembolic prophylaxis can be followed. For rate control digoxin alone has some specific limitations, therefore, use of calcium antagonists (verapamil or diltiazem) or beta-blockers must be considered. At the present time, the relative efficacy and risks of these two alternative strategies in specific patients subgroups remain to be established. Today, non-pharmacological treatments, as atrio-ventricular node ablation are also available. In elderly patients, moreover, advanced age, underlying heart disease, concomitant systemic illnesses and patient compliance to treatments condition our decision making and treatment needs to be individualized. Appropriate knowledge of the advantages, of the limitations and of the costs of every pharmacological or non-pharmacological treatment option is required for deciding in every patient in view of the best risk-benefit and cost-benefit ratio.

Serum free light-chain responses after high-dose intravenous melphalan and autologous stem cell transplantation for AL (primary) amyloidosis

Serum free light-chain (FLC) concentrations were measured by a sensitive nephelometric immunoassay in 66 patients with AL amyloidosis before and after treatment with high-dose melphalan and autologous stem cell transplantation (HDM/SCT). At 1 year after HDM/SCT, 27 patients (41%) achieved a complete hematologic response (CR), that is, disappearance of the monoclonal gammopathy previously evident by immunofixation electrophoresis (IFE) in serum and urine and of plasma cell clonality in the bone marrow. Abnormally elevated FLC levels became normal in 27 patients (41%), and decreased by >90% in 37 (56%). Average improvements in FLC were 94% for patients who achieved a CR and 72% for those who did not (P=0.0001). However, a reduction in FLC of >90% was associated with a similar high likelihood of clinical improvement and prolonged survival, whether or not patients achieved a CR. While CR, as defined by standard criteria, is a more stringent indicator of hematologic response than are decreases in abnormally elevated FLC levels per se, these measures of hematologic response are complementary, and decreases in FLC are more readily detected early after treatment than are the changes in IFE and marrow studies required to determine CR.

Minimally Invasive Thoracic Surgery for Diagnostic Assessment and Palliative Treatment in Recurrent Neoplastic Pleural Effusion

BACKGROUND

We evaluated the effectiveness of VATS in the diagnosis and palliative treatment of recurrent neoplastic pleural effusions.

METHODS

From 1987 to 2001, we performed 325 VATS chemical pleurodesis for malignant pleural effusions. We used talc in 253 subjects (78 %) and alcohol in 72 (22 %) as the sclerosant agent. In 226 patients (68 %) we performed biopsies because the histology was unknown.

RESULTS

Mean operating time was 33.38 +/- 9.77 minutes (median: 32; range: 19 - 58), and the mean duration of chest intubation was 3.78 +/- 1.33 days (median: 4; range 2 - 8). Complications occurred in 2 % of patients. Thirty-day mortality was 2 %. Mean postoperative in hospital stay was 5.53 +/- 1.90 days (median 6; range: 2 - 11). We obtained 264 (81 %) therapeutic successes (no effusion recurrence within 4 months), and 55 relapses of which 32 had talc insufflation (13 % of talc group) and 23 alcohol instillation (32 % of alcohol group).

CONCLUSIONS

VATS chemical pleurodesis is a safe, useful, versatile procedure for oncological pleural effusion management. The use of talc rather than alcohol significantly increased the therapeutic success rate. VATS should be considered the treatment of choice in patients with advanced neoplasm to obtain good palliation and a better quality of life.

[Use of the skin-closure system Medizip in median sternotomy in oncological patients. Evaluation of results obtained in 30 patients]

BACKGROUND

The authors evaluate effectiveness, safety and cosmetic results obtained using the new skin closing system Medizip.

METHODS

At the Thoracic Surgery Department of the National Cancer Institute (Milan) between June 1999 and March 2001, in 30 patients who underwent median sternotomy for bilateral pulmonary wedge resections, Medizip a new skin-closing system to suture the sternal wounds has been used. Twenty patients were under 30 (66%) and 6 of the 10 remaining were females. The average age was 34.25+/-21.60 years, (median: 25, range: 12-72). It took about half a minute (average time: 30.00+/-10.54 seconds) to perform all the application manoeuvres. In order to better evaluate the cosmetic results obtained, a scale of three levels was created: level 1: very good, level 2: satisfactory, level 3: inadequate.

RESULTS

Twenty-eight 20 cm-long zippers, one 25 cm-long and one 30 cm-long were employed. Medizip has been kept in site for 9.88+/-2.12 days on average (median: 9; range: 8-12). The time employed for each dressing was on average 70.00+/-21.35 seconds (median: 70, range: 46-128). No wound infections were observed even if all the patients were affected by neoplastic diseases and were immunocompromised because of lots of antiblastic treatments. The quick removal (few seconds) and the non-invasiveness of the disposal constitutes remarkable advantages. Using the criteria previously described, 26 patients at level 1 (87%), and 4 (13%) at level 2 were classified.

CONCLUSIONS

Medizip is considered to be an effective skin-closure system easy and quick to handle, assuring very good cosmetic results, with non-invasive removal, particularly useful in pediatric patients and in young adults affected by neoplastic diseases undergone to a lot of combined treatments.

A particular case with long-term follow-up of rare malignant hemangiopericytoma of the lung with metachronous diaphragmatic metastasis

The authors report the case of a woman with a primary hemangiopericytoma of the lung and successive metachronous diaphragmatic metastasis treated with surgery only according to the patient's decision. The patient was first submitted to left lower lobectomy with resection of diaphragm and three ribs en-bloc for pulmonary sarcoma. One year later, a chest computed tomography (CT) scan showed a small lesion above the diaphragm on the left side. She refused the proposed operation and returned fifteen months later with a new thorax CT, and told us that she had in the meantime become pregnant and given birth. A rethoracotomy to remove the metastatic diaphragmatic tumor was performed. Chemotherapy with anthracycline and iphosphamide was proposed, but the patient again refused therapy for fear of side effects impairing another pregnancy. Currently, the patient is alive and disease-free, 68 months after the first treatment. The authors emphasize the long-term follow-up obtained with surgery alone in this kind of rare sarcoma.

Major surgery in lung cancer in elderly patients? Risk factors analysis and long-term results

BACKGROUND

In the Oncological Thoracic Surgery Department of the Istituto Nazionale Tumori of Milan a retrospective study was performed on lung cancer patients 70 years old or more with the aim of evaluate the role of surgical treatment and to analyse long-term results.

METHODS

In our Institute from January 1988 to December 1993, 151 lung cancer patients 70 years old or more underwent surgery for lung cancer. One hundred and twenty-six of them (83%) were males and 25 were females (17%), the average age was 73.09+/-2.91 years (median: 77; range: 70-82). All the subjects were completely staged preoperatively. In order to establish operability criteria, we considered some selection parameters. Patients general conditions were evaluated using Karnofsky score accepting only the ones with 70% or more for surgery, all the cases performed cardio-respiratory functional evaluation. Patients with: a) FEV1 <60% of predicted value or FEV1 <1 l; b) PaO2 <60 mmHg e PaCO2 >40 mmHg were excluded from surgery.

RESULTS

The operations performed were: 23 pneumonectomies, 6 bilobectomies, 93 lobectomies, 13 segmentectomies and 16 wedge resections. Eight cases were submitted to thoracectomy in association to pulmonary resection. Peroperative mortality was 3% and morbidity was 10%. Histological examination showed 69 adenocarcinomas, 65 squamous carcinomas, 4 large cells carcinomas, 4 typical carcinoids, 5 small cells carcinomas, 2 mucoepidermal carcinomas and 2 adenosquamous carcinomas. Eighty-six patients were classified at stage I, 38 at stage II, 24 at stage III and 3 at stage IV (multifocal disease). The actuarial 4-years global survival predicted with Kaplan Meier method was 40%, in particular it was 75% for stage I patients.

CONCLUSIONS

In case of resectable primary pulmonary neoplasm, surgery represents the first choice therapy; patient's age doesn't seem to be an absolute contraindication, but it has to be evaluated with biological and not with age criteria. Using adequate selection criteria, it's possible to obtain, in patients older than 70 years, long-term survivals that don't seem to differ from global survivals.

Video-assisted thoracoscopic surgery for diagnosis, staging, and management of lung cancer with suspected mediastinal lymphadenopathy

The aim of this report was to evaluate the effectiveness of video-assisted thoracoscopic surgery (VATS) in staging, diagnosis, and treatment of lung cancer. Fifty-two patients were scheduled for mediastinal lymph node VATS biopsy at the Oncologic Thoracic Surgery Department of the National Cancer Institute in Milan. Fifty patients underwent lymph nodal thoracoscopic biopsy (96%), whereas for the other 2 patients, histologic diagnosis was done by pleural metastatic nodule thoracoscopic biopsy (4%). We performed 17 lymph nodal biopsies in level 5 (33%), 14 in level 6 (27%), 12 in level 7 (23%), and 7 in level 8 (13%). No postoperative complications were observed, and 19 subjects (36%) underwent open lung resection. The histologic diagnosis was adenocarcinoma in 25 cases (48%), epidermoid carcinoma in 14 (27%), microcytoma in 9 (17%), and giant-cell lung carcinoma in 4 (8%); 10 patients were at stage I (19%), 9 at stage II (17%), 31 at stage III (60%), and 2 at stage IV (4%). The use of VATS allowed diagnosis of the suspected involved mediastinal lymph nodes in lung cancer patients and obviated the need for painful thoracotomy, enabling accurate staging and thus selection of the optimal treatment.

[Epidemiologic data on obesity and overweight in the elderly]

The incidence and the prevalence of obesity are progressively increasing in all the more industrialized Western nations: in the USA, approximately 280,000 deaths/year are attributable to obesity. Moreover the general structure of the population to world-wide level is enduring a strong change, since it is increasing towards the bands of more advanced ages: the strong aging of population makes it necessary to deepen the behavior and the consequences of obesity as risk factor also in the third age. In Italy, overweight subjects, amounting to more than 15 million over the age of eighteen, have not increased since 1994, but the obese ones in the general population are approximately 8%. The distribution of the prevalence of obesity in the range of age between 45 and 75 does not seem to be much age correlated in the male population, while it is more age related in the women: the prevalence decreases in the last class of age. We can found a similar trend for the overweight conditions. Differences in the distribution of this important risk factor, even if often neglected, also are tied to the professional skills and education.

[Dietary restriction and oral administration of antioxidant and omega-3: what are the effects on the clinical variables in a group of obese women?]

BACKGROUND

Obesity is now recognized as a major risk factor for many pathologies. The state of obesity is associated with an increase in reactive oxygen species; persistent overconsumption of calories in the obese may be exposing them to excessive damage besides maintaining the state of obesity. It is possible that dietary modification and association with assumption of antioxidant and omega-3 oral integration contributes to a reduction in reactive oxygen species generation and a corresponding reduction in indexes of oxidative damage, including lipid peroxidation.

METHODS

Given this back-ground, the pro/anti-oxidant balance, biochemical parameters and the body composition were studied in two groups of obese women: a first group of 10 obese women were studied before and after eight weeks of dietary restriction and a second group of 12 obese women were studied before and after eight weeks of dietary restriction and oral administration of antioxidant and omega-3.

RESULTS

In summary, as regards the preliminary results of clinical outcome parameters, interestingly enough the glycemic levels fall markedly in association with both dietary restriction and oral integration with antioxidant and omega-3. Another important finding of this study is that of calcium levels and phase angle (measured by impedenzometry) increase in the group treated with dietary restriction and oral administration of antioxidant and omega-3.

CONCLUSIONS

Studies that aimed to explore whether oxidative status predicts clinical outcome would provide important details on the putative link between oxidative status and state of obesity.

Abuse of telazol: an animal tranquilizer

BACKGROUND

Telazol (tiletamine hydrochloride 50 mg/mL, zolazepam hydrochloride 50 mg/mL) is utilized in veterinary medicine as a small-animal anesthetic. Telazol is comparable to ketamine in efficacy, and in conjunction with ketamine, has been responsible for one reported human fatality. We report a case of a woman who abused telazol.

CASE REPORT

A 30-year-old female employee at a local zoo was found unresponsive by fellow workers in a clean animal treatment room. Initial reports were that she had injected veterinary-grade diazepam and telazol. On-scene paramedics reported her as obtunded and arousable to deep painful stimuli, with gag reflex intact. Systolic blood pressure was 90 mm Hg by palpation. A fresh needle puncture mark was present on her right arm; nearby were a syringe, tourniquet, and bottles of each drug. Emergency Department assessment included airway, breathing, circulation, and intravenous access. She was lavaged and given activated charcoal with a cathartic. Shortly after arrival, she became alert and oriented. Family members insisted this was not an overdose. The patient had been previously evaluated for reported episodes of syncope, "only in the evening, while at work," and was prescribed diazepam for anxiety. Product information on telazol was limited to the Veterinary Drug Physician's Desk Reference. A urine drugs-of-abuse screen was positive for benzodiazepines and cannabinoids. The patient subsequently revealed a history of recreational use of telazol. She was discharged to an in-patient detoxification facility, 12 hours postadmission.

CONCLUSION

Telazol used in veterinary medicine as an anesthetic agent, is structurally related to ketamine. Telazol causes almost immediate anesthetic effects, and sudden alertness is not uncommon as the effects of the drug subside. Urine drugs-of-abuse screens are unlikely to identify telazol. We report a veterinary worker who abused telazol.

[Food intake and nutritional status in a group of healthy elderly residing in a nursing home]

BACKGROUND

Aging is accompanied by a variety of economic, psychologic, and social changes that can compromise the nutritional status. Nutrition is an important aspect of healthful behaviour and a major component of general wellbeing of individuals throughout their life cycle. Nutritional intake appears to be an important factor contributing to aging. So, the purpose of this project was to evaluate diet and nutritional status.

METHODS

Fifty-one healthy elderly subjects aged 70 years and older (31 F and 20 M), residing in a nursing home have been studied. Nutrient intake was assessed using 24-hour recalls; nutritional status was assessed using anthropometric measurements. The nutrient intakes for individuals were compared with the Italian Recommended Dietary Allowances (RDAs).

RESULTS

Mean energy intake was 1,625 kcal; the average percentages of carbohydrate, protein, and fat were 54%, 16%, and 30%, respectively. The mean vitamin and mineral intake for participants met the RDAs except for calcium and selenium intakes. The mean fibre intake was low. The analysis of food products intake indicated that the above mentioned inadequacy in nutrient intake was the result of low consumption of milk and milk products containing calcium and a low consumption of integral foods or fruits containing fibre.

CONCLUSIONS

The significance of sound nutrition education and the adverse impact of consumer misinformation about the benefits of these food choices becomes clear with the recognition that nutritional status influences the rate of physiologic and functional declines with age. This approach will require new efforts in consumer education sensitive to the needs and beliefs of older people.

A rare complication of surgical management for esophageal tumor: a non neoplastic belated fistula between stomach and main right bronchus

The fistula between stomach and bronchus after surgery for cancer of the esophagus is a rare occurrence. We describe a gastric non neoplastic ulceration that arose late after six years from an esophagectomy, with an end-side cervical esophagogastrostomy, for a spino-cellular carcinoma. After the partial failure of surgical technique, of the endoscopic treatment and for the bad general conditions of patient we decided to treat the fistula by transluminal drainage. This technique involved a progressive resolution of the fistula, becoming, nowadays, in our division, the preferred treatment for these kinds of postoperative complications.

[Surgery in the treatment of metachronous homolateral non-small cell lung cancer]

The authors describe their experience with the surgical treatment of metachronous homolateral lung cancer by completion pneumonectomy. In the Department of Thoracic Surgery of the National Cancer Institute of Milan, over a period ranging from 1982 to 1996, 30 completion pneumonectomies were performed for local relapses or second primary tumors. The patients submitted to this intervention had a lobectomy as their first operation in 23 cases (77%), a bilobectomy in 4 (13%) and a typical segmentectomy in 3 (10%). Associated with these interventions we performed 2 en bloc chest wall resections and a contralateral wedge resection. Two subjects received neoadjuvant chemo-therapy. Histology revealed squamous carcinoma in 14 cases (47%) and adenocarcinoma in 16 (53%). Seventeen patients (57%) were classified as stage I, 8 as stage II (26%), 4 as stage III (13%) and 1 as stage IV (4%). Four patients received adjuvant chemotherapy and/or radiotherapy. Lung cancer relapse occurred as a single lesion in 27 cases (90%) and as multiple lesions in 3 (10%). We performed 18 right (60%) and 12 left (40%) completion pneumonectomies. In 1 case (4%) a sleeve pneumonectomy was necessary. Associated with these interventions we performed 5 en bloc chest wall resections. The perioperative mortality was 10% and the postoperative morbidity 40%. Histological tests showed 12 squamous carcinomas (40%) and 18 adenocarcinomas (60%). Two patients (7%) had a different histology. Disease was classified as stage I in 13 cases (44%), as stage II in 9 (30%) and as stage III in 8 (26%). Four patients received adjuvant chemotherapy and/or radiotherapy. Two subjects developed a metachronous contralateral tumor (7%). The disease-free interval was 22.70 +/- 14.69 months, with a median value of 17 months (range: 7-53 months). Mean survival after completion pneumonectomy was 49.77 +/- 49.29 months, with a median value of 26.5 months (range: 4-190 months). The 5-year actuarial survival rate, calculated using the Kaplan-Meier method, was 30%. Completion pneumonectomy is a technically very demanding intervention carrying a high risk of morbidity. On the basis of the analysis of our data, we can affirm that mean postoperative survival seems to be satisfactory and to justify this aggressive attitude towards recurrent tumor. We should stress the importance of careful evaluation of indications and precise selection of patients.

[Physiological and pathological cardiac hypertrophy]

The clinical, electrocardiographic or echocardiographic documentation of cardiac hypertrophy in hypertensive patients implies relevant interpretations concerning both the prognosis and a more precise definition of its etiology. Moreover, the finding of myocardial ischemia in these patients requires a precise diagnostic protocol directed to define whether the reduction of coronary reserve is justified by hypertension or is due to an associated coronary artery disease.

Codeine intoxication in the neonate

Although opiates can provide patients with relief from pain and the discomfort of cough, the routine prescription of these drugs for infants demands caution and concern. Infants, particularly neonates, are not merely small adults requiring smaller dosages, but rather uniquely different patients. Neonates present with an immature physiology and biochemistry with respect to drug metabolism. We report a case of codeine intoxication in the neonate, in which the drug was prescribed for cough control during an emergency department visit.

Evaluation of atrial refractoriness and atrial fibrillation inducibility immediately after internal cardioversion in patients with chronic persistent atrial fibrillation

OBJECTIVE

To prospectively evaluate right atrial refractoriness and sustained atrial fibrillation (AF) inducibility at programmed electrical stimulation in two groups of patient: a series of patients with chronic persistent AF, studied immediately after successful low energy internal atrial cardioversion, and a group of control patients without history of supraventricular arrhythmias.

PATIENTS

Nineteen patients with chronic persistent AF (mean AF duration 11 +/- 10 months, range 2-61 months) submitted to successful internal low energy atrial cardioversion in fully conscious state and 11 control patients without history of supraventricular arrhythmias.

METHODS

An electrophysiological evaluation was performed to measure atrial refractoriness and AF inducibility, by delivering single atrial extrastimuli in high right atrium, at decremental coupling, during spontaneous sinus rhythm and after 8 beats at 600, 500, 400 and 330 ms cycle length. If sustained AF was induced the protocol was terminated.

RESULTS

During programmed atrial stimulation sustained AF was induced in 8 out of 19 (42%) of the AF patients but in none of the control group. Atrial effective refractory period was significantly shorter in AF patients compared to controls both at basic cycle length, at 600 ms, 500 ms and 400 ms cycle length, meanwhile no statistically significant differences were found at 330 ms cycle length. An altered relationship between atrial effective refractory period and cycle length was found in AF patients compared to controls: the slope of linear correlation slope was significantly lower in AF group than in controls (0.04 +/- 0.07 vs 0.17 +/- 0.10, p < 0.002).

CONCLUSIONS

Marked abnormalities of atrial refractoriness and of its heart rate relationship are observed after internal cardioversion of chronic persistent AF in humans and these abnormalities are associated with an high vulnerability to AF. These observations may explain the high risk of AF recurrences in the early phases following successful cardioversion. In this scenario antiarrhythmic drug therapy seems to be mandatory for reducing arrhythmia relapses.

In vitro fertilization. Do short-term changes in estrogen levels produce increased fibrinolysis?

High estrogen levels have been implicated as a cause of thrombosis. Patients undergoing in vitro fertilization (IVF) present an opportunity to study isolated estrogen effects on the coagulation system, since hormonal manipulation is used to achieve varying estrogen concentrations. We evaluated the effect of estrogen levels on the fibrinolytic and clotting systems of 32 patients undergoing IVF from whom venous samples were obtained during a period of several weeks at baseline and retrieval times. Flow cytometric studies were performed to assay platelet activation. Hemostasis markers measured thrombin-antithrombin complexes (TAT), fibrinogen, plasmin-alpha 2-antiplasmin complexes (PAP), plasminogen activator inhibitor (PAI-1), and D-dimer. A significant decrease in PAI-1 and an increase in PAP were observed at high estrogen levels, suggesting an increase in fibrinolytic potential. However, the products of fibrinolysis, as measured by D-dimer levels, decreased at high estrogen levels. No changes were seen in platelet activation indicators or TAT levels. The fact that a decrease in products of fibrinolysis was seen at high estrogen levels despite concurrent changes in PAI-1 and PAP that normally accompany increased fibrinolysis may be due to alterations in the overall balance of the fibrinolytic system or to a delay in onset of fibrinolysis.

Transvenous internal cardioversion for atrial fibrillation: a randomized study on defibrillation threshold and tolerability of asymmetrical compared with symmetrical shocks

The aim of the study was to compare, according to a randomized cross-over design, two different biphasic waveforms (6.5/2.5 ms and 3.0/3.0 ms phases duration, respectively) for low energy internal atrial cardioversion with regard to energy requirements for cardioversion and shock induced discomfort.

METHODS

Nineteen patients with chronic persistent atrial fibrillation (AF)(mean duration 16+/-20 months) were submitted to internal atrial cardioversion (shock delivery between catheters in right atrium and coronary sinus, respectively) and were randomly allocated to baseline cardioversion with an asymmetrical biphasic shock (6.5/2.5 ms) or with a symmetrical biphasic shock (3.0/3.0 ms), according to a step up protocol. After baseline cardioversion, a sustained AF was reinduced and the patients crossed to the alternative waveform. The procedure was performed without routine administration of sedatives and shock induced discomfort was monitored by a subjective score (1 to 5). Sedatives or anesthetics were administered at patient's request.

RESULTS

The procedure was effective in all the patients and was performed without need for sedatives/anesthetics in 17/19 patients (89%). Leading edge voltage of effective shocks resulted lower for asymmetrical shocks compared to symmetrical shocks (290+/-76 vs. 337+/-104 V, P<0.001) with no statistically significant differences in delivered energy (7.74+/-4.25 vs. 8.65+/-5.94 J). Moreover shock induced discomfort resulted lower for asymmetrical shocks compared to symmetrical (pain score=4.18+/-0.73 vs. 4.59+/-0.62, P<0.02). Shock impedence of effective shocks was 59+/-10 ohms for both waveforms. No significant complications occurred during the procedure and no ventricular arrhythmia was observed after atrial cardioversion. Transient bradycardia requiring support ventricular pacing was observed in one patient.

CONCLUSIONS

Delivery of biphasic asymmetrical shocks (6.5/2.5 ms) results in lower leading edge voltage of effective shocks and better patients tolerability compared with conventional biphasic symmetrical shocks (3.0/3.0 ms). These findings are of interest both for transvenous internal cardioversion of chronic persistent AF and for implantable atrial defibrillators.

Electrophysiological effects of flecainide and propafenone on atrial fibrillation cycle and relation with arrhythmia termination

OBJECTIVES

(1) To investigate the electrophysiological effects of flecainide and propafenone during atrial fibrillation, and their relation to arrhythmia termination; (2) to investigate the effects of isoprenaline on atrial fibrillation in basal conditions and during treatment with class 1C drugs to evaluate the role of adrenergic stimulation on proarrhythmic events occurring during this treatment.

DESIGN

Prospective, single centre study.

SETTING

University hospital.

METHODS

10 patients with lone paroxysmal atrial fibrillation underwent an electrophysiological study. The dynamic behaviour of MFF (the mean of 100 consecutive atrial fibrillation intervals) was evaluated at two atrial sites after induction of atrial fibrillation either at baseline or after class 1C drug administration (flecainide or propafenone 2 mg/kg). The effects of isoprenaline on MFF and RR interval were also investigated both under basal conditions and during class 1C drug treatment.

RESULTS

After induction of atrial fibrillation, mean (SD) MFF shortened with time, and was further shortened by isoprenaline infusion (177 (22) v 162 (16) v 144 (11) ms, p < 0.05). The administration of class 1C drugs reversed this trend and significantly increased the MFF to an average of 295 (49) ms, leading to conversion to sinus rhythm within 10 minutes in all patients. Atrial fibrillation was then reinduced on class 1C drugs: isoprenaline shortened the MFF and RR interval with a trend to AV synchronisation (223 (43) v 269 (49) ms for the MFF, 347 (55) v 509 (92) ms for the RR, p < 0.05); 1:1 sustained AV conduction occurred in two patients, at 187 and 222 beats/min respectively. One of these patients underwent electrical cardioversion because of haemodynamic collapse.

CONCLUSIONS

Class 1C drugs are effective at restoring sinus rhythm by increasing the MFF to a much greater extent than observed in self terminating atrial fibrillation episodes, and reversing the spontaneous atrial fibrillation behaviour (progressive shortening of MFF and self perpetuation of atrial fibrillation). MFF prolongation with 1:1 conduction at fast ventricular rates may lead to synchronisation during adrenergic stimulation, with a very short ventricular cycle; hence it is advisable to keep the patients at rest after acute class 1C drug loading or to consider pharmacological modulation of AV conduction for patients who are prone to a fast ventricular response.

Effects of the administration of an angiotensin-converting enzyme inhibitor during the acute phase of myocardial infarction in patients with arterial hypertension. SMILE Study Investigators. Survival of Myocardial Infarction Long-term Evaluation

A positive history of arterial hypertension (HBP) is present in as many as 30% of patients with acute myocardial infarction (AMI) and their clinical outcome could be greatly improved by drugs enhancing blood pressure control and preserving ventricular function. The aim of the present study was to evaluate the importance of a history of HBP on the clinical efficacy of early treatment with the angiotensin-converting enzyme (ACE) inhibitor zofenopril in patients with anterior AMI. We summarize the results of a post-hoc analysis of data from the Survival of Myocardial Infarction Long-term Evaluation (SMILE) study, which randomly evaluated the efficacy of zofenopril given within 24 h of symptom onset to patients with anterior AMI not undergoing thrombolysis. Of 1441 patients who entered the study, 565 (39.2%) had a history of HBP. The mean follow-up time was 12 months and the main outcome measures were 6-week combined occurrence of death and severe congestive heart failure (CHF) and 1-year mortality. After 6-week of treatment with zofenopril the relative risk of death or severe CHF was 0.60 (95% confidence interval [CI]: 0.45-0.81; 2P < .05) in the hypertensive group and 0.89 (0.74-1.08; 2P = .62) for normotensive patients, whereas the 1-year risk of death was 0.61 (95% CI: 0.23,0.89; 2P < .05) and 0.77 (95% CI: 0.52-1.17; 2P = .22), respectively. The 6-week prevalence of mild-to-moderate CHF was also significantly reduced by zofenopril in the hypertensive population (14.1% v 9.4%; 2P < .05). The present data suggest that treatment with zofenopril started within 24 h of the onset of anterior AMI could be highly beneficial in patients with a history of HBP.

Coronary stenting for unstable angina: predictors of 30-day and long-term clinical outcome

BACKGROUND

Unstable angina is usually caused by acute thrombosis superimposed on a fissured plaque. Coronary artery stenting has been shown to improve short- and long-term results of coronary angioplasty in mainly stable patients with one-vessel disease, but it is uncertain whether its use in an unstable clinical setting can be safe and useful. This study sought to evaluate the results of coronary stenting in unstable angina and to determine patient, lesion and procedure-related predictors of 30-day and long-term ischemic events.

METHODS

We studied 266 consecutive patients (mean age 62 +/- 9 years) with unstable angina who underwent coronary artery stenting. The procedure was performed electively in 24%, in bailout situations in 11% and for a suboptimal result of conventional angioplasty in 65%. After stent implantation, patients were treated with anticoagulation (61) on combined antiplatelet therapy (200). Multivariate logistic regression analyses were performed to determine 30-day and long-term predictive factors of ischemic complications.

RESULTS

Procedural success was obtained in 261 patients (98.1%). During the first 30 days after stenting, one patient died from cardiogenic shock (0.3%) and six (22%) suffered a non-fatal Q-wave myocardial infarction. Patients with combined antiplatelet therapy had a significantly lower stent thrombosis rate (1.5% versus 11.4%, P = 0.002) than those treated with anticoagulant regimen. At long-term follow-up (17.7 +/- 9.4 months) cardiac mortality myocardial infarction and target-vessel revascularization rates were 0.4%, 1.5% and 9.3%, respectively. In multivessel and diabetic patients, a worse long-term event-free survival was observed. Logistic multivariate analysis revealed bailout stenting, anticoagulant therapy, implantation of stents longer than 15 mm as predictors of 30-day ischemic events. In addition, multivessel coronary artery disease and stent application with balloon size of less than 3 mm were predictive of long-term ischemic events.

CONCLUSIONS

This study demonstrates that, either electively or after failure of conventional angioplasty, coronary stenting represents an effective therapy for patients with unstable angina. In the same clinical setting, combined antiplatelet therapy is associated with a lower 30-day stent thrombosis rate than anticoagulant therapy. Bailout stenting, anticoagulant therapy, implantation of stents longer than 15 mm were shown to be predictors of 30-day ischemic events, whereas multivessel coronary artery disease and stent application with small balloon size were predictive of long-term ischemic events.

Long-term follow-up of stent implantation versus stent-like angioplasty in unstable angina

Stent-like plain old balloon angioplasty (POBA, < or = 30% residual diameter stenosis) in patients with stable angina resulted in a clinical and angiographic long-term outcome equivalent to stenting. In unstable angina POBA showed lower acute and long-term efficacy than in the stable setting. Data comparing stent-like POBA and coronary stenting in unstable angina are lacking in the literature. The aim of this retrospective single-center study was to compare the long-term effectiveness of stent-like POBA and coronary stenting in unstable angina. From January 1996 to December 1996 we retrospectively examined 187 consecutive patients with unstable angina who underwent coronary angioplasty on a native vessel: 135 had coronary stenting in addition to POBA and 50 achieved a stent-like result with POBA. Two patients, with major contraindication to coronary stenting, who did not reach a stent-like angiographic result, were also treated with only POBA but were excluded from the study. Stent implantation indications were: elective (54 stents, 30%), suboptimal angiographic result (104 stents, 58%), and bail-out situation (21 stents, 12%). Stent implantation showed high angiographic (98.5%) and clinical (95.5%) success. Stent thrombosis occurred only in 2 patients (1.5%). At quantitative coronary angiography the stent group showed a higher post-procedure minimal lumen diameter (2.74 +/- 1.25 vs 2.27 +/- 0.58 mm, p = 0.025), acute gain (1.95 +/- 1.28 vs 1.43 +/- 0.57 mm, p = 0.007) and lower residual stenosis diameter (13.89 +/- 7.43 vs 20.4 +/- 7.28%, p = 0.001) than the stent-like POBA group. At 1-year follow-up the stent group showed a higher event-free survival rate (77.9 vs 64.6%, p = 0.009) mainly due to lower recurrence of angina and repetition of percutaneous procedures. Stent-like POBA procedure and baseline lesion length > or = 10 mm proved to be the only independent predictors of long-term ischemic event occurrence. In conclusion, in unstable angina, stent implantation appears more effective than stent-like POBA to avoid long-term ischemic complications.

Effects of wave reflection timing on left ventricular mechanics

The aim of this study was to evaluate how the timing of the pressure pulse produced by peripheral reflection affects the left ventricle (stroke volume, ventricular work, coronary driving pressure). Ten isolated perfused rabbit hearts were attached to rubber tubes of different lengths (0.5, 0.8 and 1 m) connected to a hydraulic resistance. The different lengths produced reflections at different times and the reflected pulse returned to the ventricle in early (at 84 ms), middle (at 134 ms) and late systole (at 168 ms) for the three tubes, respectively. The loading parameters (ventricular filling pressure and hydraulic resistance) were not changed during the procedure. Ventricular and aortic pressure and aortic flow were monitored continuously and recorded; cardiac cycle was fixed at 800 ms. An operator-independent procedure was used to calculate instantaneous and total systolic external work, mean diastolic aorto-ventricular pressure difference and ventricular stroke volume.

RESULTS

The mean value of stroke volume for the three different length rubber tubes was 320 +/- 71, 348 +/- 77 and 368 +/- 87 microliters, respectively. The mean value of total external work was 20.3 +/- 8.3, 22.5 +/- 8.8 and 24.2 +/- 9.6 mJ, respectively. The mean aortoventricular pressure difference was 40 +/- 12, 46 +/- 13, 50 +/- 14 mmHg, respectively (1 mmHg = 133 Pa). The differences between the parameters measured in the three conditions were statistically significant (p < 0.05). A reduction of reflection timing, reduces, on a pure mechanical basis, cardiac output and external ventricular work and has a negative effect on coronary driving pressure.

Favorable effects of flecainide in transvenous internal cardioversion of atrial fibrillation

OBJECTIVES

The aim of the study was to evaluate the effects of intravenous (IV) flecainide on defibrillation energy requirements in patients treated with low-energy internal atrial cardioversion.

BACKGROUND

Internal cardioversion of atrial fibrillation is becoming a more widely accepted therapy for acute episode termination and for implantable atrial defibrillators.

METHODS

Twenty-four patients with atrial fibrillation (19 persistent, 5 paroxysmal) underwent elective transvenous cardioversion according to a step-up protocol. After successful conversion in a drug-free state, atrial fibrillation was induced by atrial pacing; IV flecainide (2 mg/kg) was administered and a second threshold was determined. In patients in whom cardioversion in a drug-free state failed notwithstanding a 400- to 550-V shock, a threshold determination was attempted after flecainide.

RESULTS

Chronic persistent atrial fibrillation was converted in 13/19 (68%) patients at baseline and in 16/19 (84%) patients after flecainide. Paroxysmal atrial fibrillation was successfully cardioverted in all the patients. A favorable effect of flecainide was observed either in chronic persistent atrial fibrillation (13 patients) or in paroxysmal atrial fibrillation (5 patients) with significant reductions in energy requirements for effective defibrillation (persistent atrial fibrillation: 4.42+/-1.37 to 3.50+/-1.51 J, p < 0.005; paroxysmal atrial fibrillation: 1.68+/-0.29 to 0.84+/-0.26 J, p < 0.01). In 14 patients not requiring sedation, the favorable effects of flecainide on defibrillation threshold resulted in a significant reduction in the scores of shock-induced discomfort (3.71+/-0.83 vs. 4.29+/-0.61, p < 0.005). No ventricular proarrhythmia was observed for any shock.

CONCLUSIONS

Intravenous flecainide reduces atrial defibrillation threshold in patients treated with low-energy internal atrial cardioversion. This reduction in threshold results in lower shock-induced discomfort. Additionally, flecainide may increase the procedure success rate in patients with chronic persistent atrial fibrillation.

Low energy internal atrial cardioversion in atrial fibrillation lasting more than a year

The aim of this study was to evaluate the efficacy of low energy internal atrial cardioversion in restoring sinus rhythm (SR) in patients with chronic atrial fibrillation (AF) persisting > 1 year. Fifteen patients with chronic AF lasting > 1 year (from 13-48 months, mean 24 +/- 13 months) were studied. R wave synchronized 3/3 ms biphasic shocks were delivered between right atrial and coronary sinus (left pulmonary artery in five patients) electrodes. Sedatives or anesthetics were administered only at the patient's request.

RESULTS

Stable SR was restored in 14 (93%) of 15 patients after shocks with a mean leading edge voltage of 377 +/- 77 V (range 260-500) and a mean delivered energy of 7.3 +/- 3.4 J (range 2.6-12.9). The procedure was performed without anesthesia in 6 (40%) patients. All successfully cardioverted patients were treated with flecainide, sotalol, or amiodarone. During a follow up of 7.7 +/- 7.9 months (range 1-24) AF recurred in five (36%) patients. Three of five AF recurrences occurred within 3 days after conversion to SR.

CONCLUSION

Internal low energy atrial cardioversion is highly effective in restoring SR even in patients with AF lasting > 1 year. The long-term results from the standpoint of freedom from AF recurrences, are satisfactory, although additional antiarrhythmic treatment is required, particularly in the first days after conversion.

Inhaled nitric oxide does not affect adenosine 5'-diphosphate-dependent platelet activation in infants with persistent pulmonary hypertension of the newborn

OBJECTIVE

To investigate the effect of inhaled nitric oxide (NO) treatment in newborns with persistent pulmonary hypertension on adenosine 5'-diphosphate (ADP)-dependent platelet activation.

METHODS

After parental informed consent, infants with persistent pulmonary hypertension of the newborn were randomly assigned to receive conventional treatment (control group) or treatment with 40 parts per million of inhaled NO. Platelet activation was measured at time of entry and 30 minutes later by surface expression of P-selectin in response to increasing concentrations of the agonist ADP (0, 2, 5, 10, and 20 microM) using fluorescence-activated flow cytometry.

RESULTS

We examined 11 infants in the inhaled NO group and 13 in the control group. P-selectin expression, quantified as mean fluorescence, was not significantly different in the two groups of patients at baseline. Median percent change from baseline fluorescence was assessed using the Wilcoxon matched-pairs signed-rank test. At 30 minutes after enrollment there were no statistically significant changes from baseline fluorescence in either group of patients and at all ADP concentrations.

CONCLUSION

Thirty minutes of exposure to 40 ppm of inhaled NO does not inhibit ADP-dependent platelet activation as measured by surface expression of P-selectin in infants with persistent pulmonary hypertension of the newborn.

The Verapamil in Hypertension and Atherosclerosis Study (VHAS): results of long-term randomized treatment with either verapamil or chlorthalidone on carotid intima-media thickness

BACKGROUND

It is unclear whether the carotid intima-media thickness can be influenced by antihypertensive treatment and whether some antihypertensive agents, such as calcium antagonists, may have a greater effect on this parameter than others, such as diuretics. The present paper reports the principal results of the ultrasound substudy of the randomized, prospective, controlled, Verapamil in Hypertension and Atherosclerosis Study (VHAS).

DESIGN AND METHODS

In 498 hypertensive patients in eight Italian centres, randomized to either verapamil (240 mg once a day) or chlorthalidone (25 mg once a day), a B-mode ultrasound scan was performed according to a standardized procedure at baseline and after 3, 12, 24, 36 and 48 months of treatment. The maximum intima-media thicknesses of the far walls of common, bifurcation and internal carotid arteries were measured bilaterally, and the following indices calculated: the mean thickness at the six measured sites, the mean thickness at the common and bifurcation sites and the single maximum thickness. The primary endpoint for treatment efficacy was the slope of the change over 4 years (rate of change, mm/year), corrected by using the initial mean over the six sites (baseline + 3 months) as a covariate (mm/year per mm). The patients were also classified into three strata according to their baseline single maximum thickness: those with normal carotid arteries (single maximum ( 1 mm), those with thickened carotid arteries (single maximum > 1 and < or = 1.5 mm and those with carotid plaques (single maximum > 1.5 mm).

RESULTS

Among the 456 patients with satisfactory baseline ultrasound readings, 33% were classified with normal carotid arteries, 27% with thickened carotid arteries and 40% with plaques. In the intention-to-treat population (377 patients with ultrasound measurements taken on at least three different occasions over a period of at least 2 years), the rate of change in the mean thickness at the six sites measured was rather small (0.015 mm/year), but significantly (P < 0.05) smaller in patients with plaques (0.003 mm/year) than in patients with thickened or with normal carotids (0.023 and 0.025 mm/year, respectively). When related to initial values, the rate of change in the mean thickness at the six sites had a negative slope (-0.059 mm/year per mm, P < 0.01). Although rates of change in the carotid intima-media thickness in unstratified patients were not different in those treated with verapamil or with chlorthalidone, when changes in the mean thickness of six sites were related to the initial value, the slope of this relationship was significantly different in the two treatment groups (verapamil -0.082 versus chlorthalidone -0.037 mm/year per mm, P < 0.02). The blood pressure-lowering effect of the two randomized treatments was similar. Taking fatal and nonfatal, major and minor cardiovascular events together, there were 19 events in the verapamil group and 35 in the chlorthalidone group, with a significantly (P < 0.01) greater incidence in patients with plaques, and among patients with plaques in those who were randomized to chlorthalidone (P < 0.05).

CONCLUSIONS

In accord with evidence from animal models of atherosclerosis, the calcium antagonist verapamil was more effective than the diuretic chlorthalidone in promoting regression of thicker carotid lesions. Changes in the carotid intima-media thickness were small in both groups, and the differences between the changes under the two treatments were consequently small, but the observation that these small differences in carotid wall changes were paralleled by differences in the incidence of cardiovascular events (better intima-media thickness regression with verapamil paralleled by a lower cardiovascular event rate) suggests that even small effects on carotid plaques may have clinical and prognostic relevance.

Conversion of recent-onset atrial fibrillation to sinus rhythm: effects of different drug protocols

In a population of 417 hospitalized patients, the efficacy and safety of different drug regimens administered to convert atrial fibrillation (AF) of recent onset (< or = 7 days duration) to sinus rhythm were evaluated. All patients were in NYHA Class < or = 2, and free of heart failure. They were randomly allocated to treatment with placebo in 121 patients; i.v. amiodarone, 5 mg/kg bolus, followed by 1.8 g/24 hours in 51 patients; i.v. propafenone, 2 mg/kg bolus, followed by 0.0078 mg/kg/min in 57 patients; p.o. propafenone, 600 mg p.o. in a single dose in 119 patients; and p.o. flecainide, 300 mg p.o. in a single dose in 69 patients. All patients were continuously monitored by Holter ECG, and the number of conversions to sinus rhythm was measured at 1, 3, and 8 hours.

RESULTS

(1) I.v. propafenone resulted in a higher conversion rate within 1 hour compared with the oral loading regimens of propafenone or flecainide, but the conversion rates at 3 and 8 hours were comparable, approximately 75% at 8 hours; 2) i.v. amiodarone was not different from placebo until 8 hours when it was associated with 57% of conversions; (3) conversion to sinus rhythm at 8 hours was observed in 37% of the placebo treated patients. Serious adverse effects occurred in few patients: two patients treated with flecainide and one treated with i.v. propafenone experienced left ventricular decompensation; one patient treated with placebo and two treated with flecainide had atrial flutter with rapid ventricular response. In conclusion, single-dose, oral loading with propafenone or flecainide are acceptable alternatives to conventional drug regimens in selected hospitalized patients. In addition, the measure of a placebo effect is mandatory in studies of recent-onset AF.

Oral loading with propafenone: a placebo-controlled study in elderly and nonelderly patients with recent onset atrial fibrillation

The efficacy and safety of propafenone as an oral loading dose (600-mg single oral dose) in converting recent-onset atrial fibrillation (< or = 7 days duration) to sinus rhythm were evaluated in a single-blind, placebo-controlled study according to patients' age. Overall, 240 hospitalized patients, NYHA Class < or = 2 without signs or symptoms of heart failure were enrolled: among patients aged < or = 60 years, 55 were allocated to propafenone treatment and 59 to placebo, respectively, and among patients aged > 60 years, 64 were allocated to propafenone treatment and 62 to placebo, respectively.

RESULTS

In each age group, the likelihood of conversion to sinus rhythm was significantly greater after propafenone compared with placebo at 3 and 8 hours. For patients aged < or = 60 years, corresponding odd ratios were 3.78 (95% CI = 1.80-7.92, P = 0.04) at 3 hours and 4.74 (95% CI = 2.12-10.54, P = 0.02) at 8 hours; for patients aged > 60 years odd ratios were 5.03 (95% CI = 2.08-12.12, P = 0.02) at 3 hours and 6.75 (95% CI = 3.28-73.86, P = 0.01) at 8 hours, respectively. Logistic regression analysis showed that conversion to sinus rhythm within 3 hours was predicted by age < or = 60 years (P = 0.0064) and by propafenone treatment (P < 0.0001), and conversion to sinus rhythm within 8 hours was predicted by age < or = 60 years (P = 0.0467) and by propafenone treatment (P < 0.0001). The occurrence of adverse effects was observed in 14%-16% of propafenone treated patients and in 8% of placebo treated patients without significant differences according to age. In conclusion, in patients with recent-onset atrial fibrillation without signs of heart failure, propafenone as a single oral loading dose is effective. It is also effective in selected elderly subjects with a favorable safety profile. Moreover, spontaneous conversion to sinus rhythm appears to occur less frequently in elderly patients.

Primary pulmonary hypertension: insights into pathogenesis from epidemiology

Primary pulmonary hypertension (PPH) is a rare disease that affects young people predominantly of female gender. Early epidemiologic studies have shown that the diagnosis is usually made 1 to 2 years after symptoms onset, and the mean survival is reduced to 2 to 3 years thereafter. New insights into the pathogenesis of PPH by epidemiologic studies may be obtained through the utilization of informatic technologies coupled to a clear definition of the disease. Early stages of precapillary pulmonary hypertension could be identified through screening tests like echocardiography in populations with higher incidence, such as familial PPH and the conditions associated with pulmonary hypertension. These latter conditions are hemodynamically and pathologically similar to the primary form, and they can give insight into several possible aspects of the pathogenesis of PPH. Prospective registries are very useful in coordinating the collection of epidemiologic data, and new technologies, such as informatics, may improve the management and the continuous updating of the databases.

Cardioverter-defibrillator oversensing due to double counting of ventricular tachycardia electrograms

We report a case of a patient with idiopathic dilated cardiomyopathy and recurrent ventricular tachycardias refractory to antiarrhythmic treatment with amiodarone. A cardioverter defibrillator implantation was performed by the transvenous technique, but ventricular tachycardia detection resulted to be inappropriate because of constant double sensing of ventricular tachycardia electrograms (QRS width=250 ms). Device programmability didn't allow a satisfactory solution to this problem, therefore a more appropriate sensing system was considered. Through an anterior thoracotomy two epicardial wires were positioned and sensing by these wires, placed closer to ventricular tachycardia origin, resulted appropriate. An electrophysiologic study and subsequent follow up confirmed appropriate ICD detection of ventricular tachycardias. This case emphasizes how in some cases sensing by epicardial wires may be a solution for QRS double counting occurring with endocardial leads during ventricular tachycardia.

Short- and long-term effects of early fosinopril administration in patients with acute anterior myocardial infarction undergoing intravenous thrombolysis: results from the Fosinopril in Acute Myocardial Infarction Study. FAMIS Working Party

BACKGROUND

Angiotensin-converting enzyme inhibitors are used in patients who have myocardial infarction with left ventricular (LV) dysfunction. Few data are available in patients whose LV function is within the normal range.

METHODS AND RESULTS

The Fosinopril in Acute Myocardial Infarction Study was a 2-year, randomized, double-blind, placebo-controlled, multicenter study of 285 patients with anterior acute myocardial infarction and was designed to investigate the effects of the early (<9 hours) administration of fosinopril and thrombolysis on (1) changes in echocardiographically evaluated LV volumes at 3 months and (2) long-term occurrence of death and congestive heart failure. LV volumes were normal at baseline in more than 70% of patients and were comparable between groups both at baseline and after 3 months of treatment. Fosinopril-treated patients showed a 30% reduction in the 2-year combined prevalence of death or moderate-to-severe congestive heart failure (New York Heart Association class III-IV) despite having a worse clinical profile at baseline. The benefit of fosinopril was confirmed both in patients without congestive heart failure at admission and in those with ejection fraction >40% at baseline. Moreover, the incidence of significant ventricular arrhythmias was lower in the fosinopril group (0.8% vs 6.0%, p < 0.02).

CONCLUSIONS

The results of the Fosinopril in Acute Myocardial Infarction Study suggest that early treatment with fosinopril can benefit patients with acute myocardial infarction in addition to a prevention of LV remodeling.

Risk factors associated with alterations in carotid intima-media thickness in hypertension: baseline data from the European Lacidipine Study on Atherosclerosis

BACKGROUND

The possibility that calcium antagonists exert an anti-atherosclerotic action at least partly independently of the blood-pressure-lowering effect is supported by results of a large number of experimental studies and can now be investigated by quantitative B-mode ultrasound imagining of the carotid artery walls.

DESIGN

The European Lacidipine Study on Atherosclerosis (ELSA) is a prospective, randomized, double-blind, multinational trial comparing effects of 4-year treatment based on the long-acting, highly lipophilic calcium antagonist lacidipine with those of treatment based on the beta-blocker atenolol on the development of carotid artery wall alterations in patients (aged 45-75 years) with mild-to-moderate hypertension (systolic blood pressure 150-210 mmHg and diastolic blood pressure 95-115 mmHg). While the intervention study is progressing, this article summarizes baseline data obtained from the whole cohort of 2259 patients randomly allocated to treatment.

METHODS

Baseline ultrasound data were obtained from two replicate examinations performed shortly before random allocation to treatment by certified sonographers at 23 referral centres and read at the ultrasound coordinating centre at the Wake Forest University School of Medicine. Intima-media thickness was measured at up to 12 different sites in the carotid artery tree and expressed as the mean of the maxima at these sites (Mmax), the mean of the maxima at four sites in the distal common carotid artery and bifurcation (CBMmax) and the maximum intima-media thickness (Tmax). Baseline demographic and clinical measurements were performed by investigators in 410 peripheral clinical units and 24 h ambulatory blood pressure monitorings read and validated by members of a centralized unit at the University of Milan. The statistical analysis centre at the Technische Universität München received and analysed all baseline data, by calculating means +/- SD, medians and ranges and performing correlation (Spearman correlation coefficients) and multiple regression analyses.

RESULTS

Prevalence of carotid artery wall alterations among the hypertensive patients randomly allocated to treatment in the ELSA was very high: 82% had Tmax > or = 1.3 mm ('plaques' according to protocol) and 17% had Tmax > or = 1.0 and < 1.3 mm ('thickening'), with a median of two plaques per patient. We found significant correlations between ultrasound measurements and the following demographic and clinical variables: age, sex, systolic blood pressure and pulse pressure (both clinic and ambulatory), concentrations of total, high-density lipoprotein and low-density lipoprotein cholesterol and triglycerides, smoking habit and duration of hypertension. We found no significant correlation to diastolic blood pressure and glucose concentration. A multiple regression analysis indicated significant variables in the following rank order: age, 24 h ambulatory pulse pressure, sex, low-density lipoprotein cholesterol concentration, triglyceride concentration, smoking and clinic systolic blood pressure.

CONCLUSIONS

Analysis of baseline data from the ELSA has shown that there is an extremely marked prevalence of carotid artery wall alterations among mild-to-moderate, middle-aged hypertensive patients. In addition to age, systolic blood pressure and pulse pressure, particularly if they are accurately measured by ambulatory monitoring, play a major role, somewhat greater than those of sex, low-density lipoprotein cholesterol concentration and smoking, in influencing intima-media thickness.

Antithrombotic therapy after coronary stent placement

Subacute stent thrombosis and hemorrhagic complications due to intensive anticoagulant therapy limit the clinical benefit of coronary stenting. Antithrombotic therapy after coronary stent placement has not been standardized yet. From January 1994 to December 1995 a total of 338 Palmaz-Schatz stents were implanted in 285 patients. Procedural success rate was 98.8%. In the initial period, after stent placement, patients were treated with acetylsalicylic acid (ASA) and warfarin (135 patients, Group A), while subsequently, according to the results of other studies, patients were treated with ASA plus ticlopidine (146 patients, Group B). Two hours after sheath removal, Group A patients were treated with intravenous heparin until therapeutic INR (2.5-3.5) was reached; warfarin was stopped 3 months later. In Group B patients 2 hours after sheath removal a treatment with subcutaneous heparin 25,000 IU/die plus ticlopidine 500 mg/die was started. Subcutaneous heparin was maintained until hospital discharge, ticlopidine was stopped after 1 month and ASA was maintained indefinitely. There were no significant differences in baseline characteristics between the two groups. Most patients had unstable angina and in the majority of cases the stent was implanted due to intimal dissection after balloon dilation. Eleven patients had subacute thrombosis of the stent (3.9%): 9 patients were in Group A (6%) and 2 patients were in Group B (1.3%; p = 0.04). Seven patients (6 in Group A, 1 in Group B) were treated with emergency coronary angioplasty and 3 (2 in Group A, 1 in Group B) with coronary bypass; nevertheless 7 patients (6 in Group A, 1 in Group B) had an acute myocardial infarction. Eight patients (6 in Group A, 2 in Group B) had major bleeding due to a large groin hematoma requiring blood transfusion or vascular surgery. In conclusion, after coronary stenting antithrombotic therapy with ASA plus ticlopidine, as compared with anticoagulant therapy, reduces the incidence of both cardiac events and hemorrhagic complications.

Prevalence of episodes of ST-segment depression among mild-to-moderate hypertensive patients in northern Italy: the Cardioscreening Study

OBJECTIVES

To assess the prevalence of episodes of ST-segment depression in a population of consecutive patients with mild-to-moderate essential hypertension who are free of clinical signs of coronary artery disease.

METHODS

The study involved 28 Italian centers that enrolled 414 hypertensive patients (aged 50-70 years; diastolic blood pressure > or = 95-115 mmHg or systolic blood pressure > or = 150-220 mmHg, or both, 10 days after withdrawal of medications). Silent myocardial ischemia was assessed by means of exercise stress testing and 48 h Holter monitoring. An ischemic episode was defined as a horizontal or downward sloping ST-segment depression > or = 100 microV, occurring 80 ms after the J point, and lasting for at least 1 min.

RESULTS

Of the 414 patients enrolled, 411 completed the exercise stress test. During the test significant ST-segment depression occurred for 25 patients (6.1%) and all episodes but one were asymptomatic and not associated with arrhythmias. Of the 396 patients for whom we analyzed a 48 h Holter recording, 43 (10.9%) had at least one episode of ST-segment depression and seven of these had also had one during the exercise stress test The median number of episodes per patient was five (range 1-19), median duration was 9 min (range 1-20 min), and the mean amplitude of the ST-segment depression was 190 +/- 180 microV. None of these episodes was associated with symptoms and all of them occurred under resting condition. Patients with (n = 61) and without (n = 335) ST-segment depression during Holter monitoring or exercise stress testing had similar ages (59 +/- 6 versus 58 +/- 6 years) and did not differ for tobacco smoking, plasma lipid levels, blood pressure values and prevalence of echocardiographic left ventricular hypertrophy (57% of patients had left ventricular mass indexes > or = 134 g/m2 for men and > or = 110 g/m2 for women in both groups). Women had a higher prevalence of ST-segment depression than did men during Holter monitoring [32 of 183 (17.5%) versus 11 of 213 (5.2%)], whereas the prevalences of ischemia during the exercise stress test were similar. Female sex was the only significant factor associated with the occurrence of silent myocardial ischemia [odds ratio 2.56 (95% confidence interval 1.40-4.71)].

CONCLUSIONS

Our results show that 15% of patients with mild-to-moderate hypertension, who are free of clinical signs of coronary artery disease, experience episodes of ST-segment depression during Holter monitoring or exercise stress testing. Most of these episodes are asymptomatic and are not associated with the severity of hypertension, the presence of left ventricular hypertrophy, and other risk factors for coronary artery disease. Episodes of ST-segment depression are more common for women than they are for men, particularly during Holter monitoring. The early detection of silent myocardial ischemia by Holter monitoring or by the exercise stress test might be useful for the identification of hypertensive patients who should be investigated further and administered a more specific treatment.

Platelet and neutrophil activation during cardiac surgical procedures: impact of cardiopulmonary bypass

BACKGROUND

Platelet and neutrophil activation plays a crucial role in reperfusion injury. To determine whether platelet and neutrophil activation occurs in the coronary circulation after cold cardioplegic arrest and reperfusion, we studied 22 patients undergoing coronary artery bypass or valve procedures, or both procedures.

METHODS

Blood was sampled from the coronary sinus and the radial artery (A) before bypass; (B) immediately after cross-clamp release; and (C) 5 minutes after cross-clamp release; and was analyzed for surface markers of platelet (CD62P) and neutrophil (CD11b) activation.

RESULTS

During bypass, platelet activation increased significantly (p < 0.01) over prebypass values, but no difference was seen between arterial and coronary sinus samples. Neutrophil activation also increased significantly (p < 0.001) during bypass, but there was no difference between arterial and coronary sinus samples.

CONCLUSIONS

Cellular activation occurs locally in the coronary circulation during bypass, but no more so after cold cardioplegic arrest and reperfusion.

N-acetylcysteine reduces methemoglobin in an in-vitro model of glucose-6-phosphate dehydrogenase deficiency

OBJECTIVE

To determine whether N-acetylcysteine (NAC) reduces methemoglobin (MHB) in an in-vitro model of glucose-6-phosphate dehydrogenase (G6PD) deficiency, given that methylene blue is an ineffective MHB antidote in G6PD deficiency.

METHODS

Five volunteers donated blood, which was divided equally into 2 test tubes, centrifuged, and washed with Tris-Mopps buffer (pH 7.4, 15 mmol/L glucose). Both tubes were incubated with epiandrosterone (EA) (400 micromol), a specific inhibitor of G6PD. After 75 microL of 0.18 mol hydroxylamine (HA) was added to induce MHB formation, 150 microL of NAC (20 mg/mL) was added to tube 1 and 150 microL of phosphate-buffered saline (PBS) was added to tube 2 as a volume control. Serial MHB levels are reported as a percentage of total hemoglobin (Hb). G6PD activity was measured at baseline, 15 minutes after EA, and at 5 hours.

RESULTS

Mean G6PD activity at baseline was 9.2+/-2.9 U/g Hb (normal >4.6 U/g Hb); 15 minutes after EA was 3.0+/-1.0 U/g Hb; and at experiment's end was 2.3+/-0.7 U/g Hb. The mean (+/-SD) areas under the concentration-time curves (AUCs) of NAC-EA-HA and PBS-EA-HA samples were compared using an unpaired t-test and were significantly different: PBS-EA-HA, 20,400+/-1,100 % min, vs NAC-EA-HA, 10,400+/-1,000 % min, respectively (p < 0.05).

CONCLUSION

In this in-vitro model of G6PD deficiency, NAC efficiently reduced MHB.

Efficacy and tolerability in fully conscious patients of transvenous low-energy internal atrial cardioversion for atrial fibrillation

Transvenous low-energy atrial cardioversion was performed in a series of fully conscious patients (30 patients with chronic atrial fibrillation and 5 patients with paroxysmal atrial fibrillation). The results show that internal atrial defibrillation is effective and tolerable in most patients.

[Endocoronary stent: its use to improve suboptimal outcome of angioplasty]

BACKGROUND

This single-center report describes the results of unplanned coronary stenting for the treatment of suboptimal angiographic results after conventional coronary angioplasty (PTCA), Suboptimal results of PTCA were defined as: a) residual stenosis > or = 30% with TIMI flow 3; b) presence of coronary dissection < 15 mm with TIMI flow 3.

PATIENTS

From January 1994 to December 1995, 213 patients with suboptimal result of PTCA underwent coronary stent implantation.

RESULTS

Stenting resulted in a technical and angiographic success in 99.5% of patients. In-hospital complications involved acute myocardial infarction (2.3%), coronary artery bypass grafting (1.4%), re-PTCA (2.3%) and vascular complications at the puncture site (1.4%). No deaths occurred. The in-hospital complication rate was similar in the groups of patients stented for coronary dissection or residual stenosis > or = 30%. Instead, the combined antiplatelet treatment group showed lower rates of subacute stent thrombosis (0.8 vs 8.9%; p = 0.011) and major complications (1.6 vs 10%; p = 0.016) than the ASA-warfarin treatment group. At a six-month follow-up, clinical restenosis was detected in 9.5% of patients. Re-PTCA was performed in 7.1% of patients and elective coronary bypass grafting in 2.8%. No acute myocardial infarction occurred and one patient presented a non-cardiovascular death. At the end of the follow-up, only 5.2% of the patient were still symptomatic.

CONCLUSIONS

The unplanned use of intracoronary stenting for the treatment of suboptimal result of PTCA improves the immediate angiographic result, reducing the procedural complication rate with good short- and long-term clinical results.

Clinical results of the Verapamil inHypertension and Atherosclerosis Study. VHAS Investigators

OBJECTIVE

The Verapamil in Hypertension and Atherosclerosis Study (VHAS) is a prospective randomized study the objective of which was to compare the long-term effects of verapamil and chlorthalidone on the blood pressure, clinical safety, and the progression/regression of carotid wall lesions in members of a large population of hypertensive patients.

DESIGN

After a 3-week placebo run-in period, 1414 hypertensive patients [692 men and 722 women, aged 53.2 +/- 7 years, blood pressure 168.9 +/- 10.5/ 102.2 +/- 5.0 mmHg (means +/- SD)] were assigned randomly to be administered either 240 mg sustained-release verapamil (n = 707) or 25 mg chlorthalidone (n = 707) once a day for 2 years. The study design was double blind for the first 6 months and open thereafter. 25-50 mg/day captopril were added to the treatment of non-responding patients; subsequently, patients not responding to combined therapy were switched to any therapy chosen by the treating doctors (free therapy). The blood pressure of the sitting subject, heart rate, and a standard clinical safety profile (electrocardiogram, laboratory tests, adverse events, cardiovascular events, and deaths) were assessed regularly throughout the study.

RESULTS

After 2 years the systolic and diastolic blood pressures were reduced significantly in members of both treatment groups (by 16.3/16.6% with verapamil and by 16.9/16.2% with chlorthalidone, both by analysis of variance, P < 0.0001). The patients for whom we added captopril treatment constituted 22.6% of the verapamil and 26.2% of the chlorthalidone group; while 11.6 and 12.2% of patients in these groups, respectively, were administered free therapy. Normalization of the diastolic blood pressure (to < or = 90 mmHg or to < or = 95 mmHg with a > or = 10% decrease) was achieved for 69.3% of the verapamil and 66.9% of the chlorthalidone group. A decrease in heart rate (by 5.8%) occurred in members of the verapamil group only. A decrease in total serum cholesterol (from 223.6 to 216.9 mg/dl, P < 0.01) and in the total cholesterol: high-density lipoprotein cholesterol ratio (from 4.9 to 4.5, P < 0.01) was noted for the verapamil group only, whereas significantly greater rates of hyperuricemia (plasma urate > 7.0 mg/dl; 10.8 versus 3.9%) and hypokalemia (serum K < 3.5 mmol/l; 24.6 versus 4.4%) were observed for the chlorthalidone group (P < 0.01, versus verapamil for both). Adverse events were reported by 32.5% of patients treated with verapamil and by 33.4% of those treated with chlorthalidone. The most frequent adverse events were constipation in members of the verapamil group (13.7%) and asthenia in members of the chlorthalidone group (8.5%). In total 315 dropped out (153 from the verapamil and 162 from the chlorthalidone group). The occurrence of cardiovascular events was similar for both treatments (42 events for verapamil and 43 for chlorthalidone, NS).

CONCLUSION

Similar antihypertensive efficacies, tolerabilities and cardiovascular event rates were observed with verapamil and with chlorthalidone. However, treatment with chlorthalidone was associated with significantly higher incidences of hyperuricemia and hypokalemia than was treatment with verapamil.