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Biomedical subjects

G Vergara

Publications and source records attributed to G Vergara.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Hemodynamic and coronary angiographic performance at a center with medium-low activity: organization model, activity indicators, and costs].

BACKGROUND: In order to evaluate the cost-effectiveness of coronary angiography performed in a low volume Center, we examined our 1-year activity. METHODS: The organizational model of the multipurpose cardiac catheterization laboratory is described. In this type of facility both coronary angiographic and electrophysiological studies are performed. To evaluate the laboratory performance we examined the utilization level, the appropriateness of the studies, the complication rates and the number of studies that had to be repeated because of inadequate data or image quality. The costs were calculated for the in-house laboratory setting (the actual scenario) and for the 25 km distant laboratory setting (the historical scenario). RESULTS: The laboratory caseload of coronary angiography was 342 studies, 46% of the overall laboratory activity; 175 patients (51%) underwent non-pharmacological therapy, 129 patients (38%) were treated with medical therapy; the percentage of patients with normal coronary arteries was 11%. Two patients (0.58%) had vascular complications, 1 patient (0.29%) developed an acute myocardial infarction 2 hours after coronary angiography without any evidence of angiographic modifications at the repeated study. In no patient the study had to be repeated because of inadequate data or image quality. The mean cost of a coronary angiography was Lit. 512,000 (265 Euro) for the actual scenario; it would have been Lit. 694,000 (359 Euro) for the historical scenario, with Lit. 182,000 (94 Euro) saved. CONCLUSIONS: These findings are consistent with the accepted criteria of good laboratory performance and cost-effectiveness. Thus coronary angiography can be performed effectively and efficiently in a low volume Center.

Cardiac Care Facilities↗
PubMed2000

[Efficacy of treatment with rt-PA of massive pulmonary embolism in patients with contraindications for thrombolytic therapy].

Pulmonary embolism is a life-threatening condition that is accompanied by significant morbidity and mortality. In massive pulmonary embolism, where restoration of pulmonary arterial flow is urgently required, the only options available are surgical thromboembolectomy and/or thrombolytic therapy. Unfortunately, a large part of thromboembolic diseases is also considered as an absolute or relative contraindication to thrombolysis. The purpose of this paper was to emphasize the possibility of new thrombolytic agents of disregarding, according to circumstances, the contraindications to thrombolytic treatment.

Aged↗
PubMed1999

[Myocardial infarct with ST segment depression: an absolute contraindication to thrombolytic therapy?].

The benefit of thrombolytic reperfusion has been demonstrated widely in patients who present with ST segment elevation and develop myocardial infarction. Instead, the role of thrombolytic therapy in patients who present with ST segment depression and develop myocardial infarction is still unresolved. The purpose of this paper is to review the literature on the subject and give rise to reconsideration of thrombolytic therapy in this subgroup of patients who are usually excluded from receiving thrombolytic agents because of the absence of indications and the presence of contraindications.

Angioplasty, Balloon, Coronary↗
PubMed1998

Catheter ablation of Wolff-Parkinson-White syndrome associated with congenital absence of inferior vena cava.

In the present report we describe a patient (a 36-year-old woman with 15 year history of supraventricular tachyarrhythmias) with congenital absence of inferior vena cava (IVC) revealed during radiofrequency (RF) catheter ablation procedure for right postero-septal Wolff-Parkinson-White syndrome (WPW). For the absence of IVC, the ablation procedure was more difficult, because we had to perform the ablation with the catheters (the ablator catheter and the coronary sinus catheter) introduced both through the superior vena cava. The application of RF energy (35 Watt for 60 seconds) at successful site abolished accessory pathway conduction. The following day was performed the venous angiography, showing the absence of the IVC and a venous return via paravertebral venous plexus to the azygous vein and superior vena cava into the right atrium. Computer tomography confirmed the absence of the IVC with azygous continuation. The drainage via the azygous system modified the radiological image on chest roentgenogram of the right mediastinal silhouette. During cardiogenesis fusion of the IVC and organisation of the heart occur between the 33rd to 40th embryonic days. It is therefore possible that some unknown teratogenic mechanism at this critical period might have caused, in the patient, both the developmental arrest of IVC and failure of regression of atrio-ventricular anatomical and electrical continuity in the right postero-septal region.

Abnormalities, Multiple↗
PubMed1998

[Intramural aortic hematoma].

Aortic dissection is a medical and/or surgical emergency that is usually catastrophic if not diagnosed and treated promptly. Transesophageal Doppler echography provides an accurate method of diagnosing and evaluating dissection of aortic aneurysm. Due to the high resolution of transesophageal echocardiography, special subtypes of aortic dissection such as intramural hemorrhage can be diagnosed. The purpose of this paper is to report a case and review the anatomical, clinical and transesophageal echocardiography aspects of aortic dissection without intimal rupture (intramural hematoma).

Aged↗
PubMed1998

[An Italian experience of radiofrequency transcatheter ablation in type-I atrial flutter: the results and follow-up].

BACKGROUND: Type I atrial flutter (AF) is a supraventricular tachycardia that is notoriously disabling and resistant to antiarrhythmic drugs. The introduction of an effective non-pharmacologic technique, such as radiofrequency catheter ablation (RF), opened new therapeutic prospects for the management of this arrhythmia. The aim of our study was to evaluate the long-term efficacy of atrial flutter RF using a successful procedure marker of bi-directional conduction block in the isthmus. METHODS: In the last consecutive 50 patients (pts) who underwent RF procedure for AF at our Center (46 pts during spontaneous or induced AF and 4 in sinus rhythm) after the successful interruption of AF we performed the usual reinduction attempts and well atrial pacing from 2 sites in the right atrium (in 18 pts before and after RF and in 32 only after RF). The sites of pacing were site 1: low lateral right atrium (LRA); site 2: proximal coronary sinus (PCS). The 50 pts consisted of 13 females, 37 males with a mean age of 62.5 +/- 9.7 years (35-83). The end-point for the procedure was: 1) abrupt interruption of AF; 2) inability to reinduce AF; 3) recognition of atrial activation sequence during pacing in LRA and in PCS compatible with conduction block in the isthmus. RESULTS: The RF was successful in terminating AF in all pts after 11 +/- 7 applications of energy. After ablation, sustained AF was no longer inducible by atrial pacing. After RF, during pacing in sinus rhythm from LRA, the lower septum and PCS presented a delayed activation after the His region. Similarly, during pacing from PCS after ablation, the atrial activation sequence was modified: the low lateral right atrium was now activated by a single front after the high lateral atrium. No acute complications were noted in any pts during or after procedure. AF recurred in 9 pts. Four pts now present chronic atrial fibrillation. The mean follow-up period is 14.8 +/- 8 months. All the patients were discharged without antiarrhythmic therapy. CONCLUSIONS: The mechanism of successful ablation is the bi-directional conduction block in the isthmus with the evidence of the changes in the right atrial activation sequence during atrial pacing in sinus rhythm in LRA and in PCS before and after RF.

Adult↗
PubMed1997

Cytogenetic findings in 73 osteosarcoma specimens and a review of the literature.

Tumor-specific chromosomal abnormalities have been identified in several histologic subtypes of sarcomas. Characterization of recurrent chromosomal abnormalities has provided direction for molecular investigations of pathogenetically important genes. Cytogenetic reports of osteosarcoma, the most common primary malignant bone tumor, are relatively rare. In this study, 73 osteosarcoma specimens from 51 patients were cytogenetically analyzed following short-term culture. Clonal chromosomal abnormalities were detected in 47 and included one haploid specimen, 18 near-diploid specimens, 17 near-triploid, 8 near-tetraploid, 1 near-hexaploid, and 2 specimens with multiple clones of different ploidy levels. Examination of the present data and previously published data (111 clonally abnormal osteosarcoma specimens) reveals that chromosomal bands or regions 1p11-13, 1q10-12, 1q21-22, 11p15, 12p13, 17p12-13, 19q13, and 22q11-13 are most frequently rearranged and the most common numerical abnormalities are +1, -9, -10, -13, and -17. Partial or complete loss of the long arm of chromosome 6 also was seen in all cases of the present study and all previously published cases describing structural abnormalities of 6q. Parosteal osteosarcoma, a prognostically favorable osteosarcoma subtype, was characterized by the presence of a ring chromosome accompanied by no or few other abnormalities. Complex karyotypes were seen nearly exclusively in the high-grade lesions. These findings indicate that specific chromosomal bands and/or regions are nonrandomly involved in osteosarcoma and may provide useful clinical information.

Adolescent↗
PubMed1997

Meningiomas intrinsic to the geniculate ganglion.

OBJECTIVE: To present the clinical, surgical and histopathological manifestations of meningioma intrinsic to the geniculate ganglion. STUDY DESIGN: Retrospective study of outcome. SETTING: Three private tertiary and one university (otology/neurotology) referral centers. PATIENTS: Six patients with cranial nerve VII paresis underwent magnetic resonance imaging and/or high-resolution computed tomography for subsequently histologically proven intrinsic meningioma of the geniculate ganglion. An additional six cases were identified in the literature. Most patients were female and ranged in age from 5 to 40 years. INTERVENTION: Total tumor removal via middle fossa and mastoid exposures followed by cable graft VII-VII neuroanastomosis. MAIN OUTCOME MEASURE: Meningioma can occur intrinsic to the geniculate ganglion and produces gradual VIIth nerve paresis as its first symptom. Other sites of predilection may occur extrinsically within the temporal bone or along intracranial venous sinuses at sites of arachnoid villi. RESULTS: Hearing was maintained in each patient, and postoperative House-Brackmann grade III-V facial nerve function was achieved. CONCLUSIONS: Intrinsic meningiomas of the geniculate ganglion rarely occur. However, this entity should be included in the differential diagnosis of a slowly progressive VIIth nerve paresis, especially in young females. Surgical removal and cable graft VII-VII neuroanastomosis is the treatment of choice. Long-term follow-up should be maintained because of the potential for von Recklinghausen's disease.

Adolescent↗
PubMed1994

[Posterior cranial fossa hemorrhage in term newborn infants: clinical and ultrasonographic aspects in 2 cases].

Haemorrhages of the posterior cranial fossa were diagnosed by cerebral sonography, sometimes these lesions were misinterpreted by the examination. We report two cases of posterior fossa haemorrhages in the term newborn without ultrasonography signs of this pathology. In a case some days after haemorrhagical damage, the signs of past haemorrhage were demonstrated.

Cerebral Hemorrhage↗
PubMed1994

[Abnormalities of cardiovascular baroreflex control in renal failure and cardiac insufficiency. Experimental study and brief critical review of the literature].

We attempted to determine the relevance and relative prevalence of autonomic dysfunction in 7 patients with end-stage renal disease (ESRD) but no heart disease, 8 patients with left ventricular dysfunction (LVD) with no renal disease and 8 patients with ESRD + LVD. In each group, the assessment of autonomic function and location of the lesion was performed by using the baroreflex sensitivity tests, based upon heart rate (ie Valsalva, deep breathing, lying to standing) to study the parasympathetic system as well as based upon blood arterial pressure (ie standing and sustained handgrip) to evaluate the sympathetic system. The same tests were performed in 7 healthy volunteers enrolled as control group. Separate studies were performed on the efferent parasympathetic arc (atropine test) and the efferent sympathetic arc (cold pressor test). There was evidence of parasympathetic damage in 100% of ESRD patients, in 87.5% of ESRD + LVD patients, and in 62.5% of LVD. Only 1 of ESRD patients showed defective response to atropine whereas the remaining had a normal response, suggesting an afferent lesion alone. No abnormalities were found in the response to cold pressor test, thereby suggesting a lack of involvement of the efferent sympathetic arc. The response to handgrip was higher in LVD patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

[Psychological status of patients with implantable cardioverter-defibrillators].

BACKGROUND: We assessed the psychological status of 20 patients (19 male, 1 female; mean age 61 +/- 9.3) with implantable cardioverter-defibrillator (ICD). Each patient underwent the Cognitive Behavioral Assessment adapted for Hospital use (CBA-H), and completed an ad hoc 20 item questionnaire designed to measure patients' perceptions of their health. METHODS: Psychological variables were treated as dependent variables and cardiac variables were considered independent variables in the one-way analysis of variance; when psychological and cardiac variables were discrete variables, Chi-square was used; correlations were performed by rank Spearman test. RESULTS: Indicated maladaptive behaviours in on 35% of the sample. Patients with pre-ICD Ventricular Fibrillation (VF) or Sustained Ventricular Tachycardia (SVT) and VF were the most psycho-physically distressed (p < .02). These were also the patients who reported feeling most stressed in the last three months (p < .03). I-E causal attribution is a psychological dimension related to the way of codify an event; I = internal means that subject attributes to itself the cause of what happens; E = external means that subject attributes to others, fate and environment what happens. The treatment received and the I-E causal attribution were found to correlate: Internal in patients who underwent both pacing and shock treatment (who were also those with the highest number of recurrent VT/VF episodes), External in patients who underwent one treatment or none (F3, 16 = 3.28; p < .04; I-E mean = 1 +/- .63 in pacing/shock treatment group; I-E mean = 2.5 +/- .57 in shock treatment group; I-E mean = 1.8 +/- .5 in pacing treatment group; I-E mean = 2 +/- .1 in no treatment group. The time since implantation (5-9, 10-18, 19-32 months) seemed to have an important effect, even if it reached statistical significance in only two areas, namely: family relationships which were better in patients who had the ICD for > 9 months, and adjustment to the physical condition, which was better in patients who had the ICD for 10-18 months. CONCLUSION: In the present study most of the patients with ICD proved to be fairly well-adjusted to their physical condition. The preimplantation cardiac condition, the treatment received, the number of recurrent VT/VF episodes, and the length of follow-up turned out to be the variables which most influenced the psychological status of patients with ICD.

Adult↗
PubMed1992

Long-term follow-up of patients with inducible supraventricular tachycardia treated with flecainide or propafenone: therapy guided by transesophageal electropharmacologic testing.

We report our experience with flecainide and propafenone therapy for inducible supraventricular tachycardias and paroxysmal supraventricular tachycardias due to atrioventricular (AV) nodal reentry or the Wolff-Parkinson-White syndrome. We performed an electropharmacologic test (ET) that consisted of first inducing a clinical arrhythmia by transesophageal atrial pacing (TAP) protocol. This was followed by intravenous drug administration and TAP reevaluation, either after acute intravenous administration or in oral steady-state. We used ET with flecainide and/or propafenone to study 2 groups of patients at least 3 years before the long-term clinical observation period. The first group was comprised of 58 patients with reciprocating tachycardias--due to AV node reentry in 17 (29.3%) and anomalous pathway in 41 (70.7%). Twelve (29.3%) of the latter had reciprocating tachycardias, 15 (36.6%) had atrial fibrillation, and 14 (34.2%) had both arrhythmias. During ET, flecainide was administered to 42 patients, and the ET was considered positive in 28 (66.7%). Propafenone was administered to 32 patients, with positive results in 15 (46.9%). In 15 patients, both flecainide and propafenone were tested, 8 receiving flecainide after a negative ET with propafenone, and 7 receiving propafenone after a negative ET with flecainide. In the first group, the ET was positive in 7 (87.5%), and in the second group, it was positive in 3 (42.9%). In a follow-up of 40.1 +/- 11 months, 38 (65.5%) patients had positive outcomes, 5 (8.6%) had to stop receiving the drugs because of side effects, 3 (5.2%) stopped because of inefficacy, and 12 (20.7%) dropped out.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Electropharmacological testing by transoesophageal atrial pacing in inducible supraventricular tachyarrhythmias. A good approach for selection of long-term anti-arrhythmic therapy.

Sixty-eight patients with disabling episodes of inducible supraventricular tachyarrhythmia were tested electropharmacologically by transoesophageal atrial pacing. Using this technique we induced clinical arrhythmia in 67 (98.5%); 26 (38.8%) had a reciprocating tachycardia due to AV node reentry and 41 (61.2%) a by-pass tract. In the latter we induced a reciprocating tachycardia in 12 (29.3%), atrial fibrillation in 25 (36.5%) and both in 14 (34.2%). We then performed an anti-arrhythmic drug test and a transoesophageal reevaluation either after acute intravenous drug administration or during oral steady state. Altogether we tested 111 drugs or a combination of drugs before the results were considered positive; all patients tolerated the procedure well and were discharged with the drug or combination of drugs judged effective. At follow-up of 16.6 +/- 8.5 months, 42 patients (62.7%) were symptom-free, 17 (25.3%) had minor and non-disabling relapses, six (9%) stopped the drug because of inefficacy (1-1.5%) or side effects (5-7.5%); two (3%) dropped out. We conclude that electropharmacological testing with transoesophageal pacing constitutes a very good approach for inducible supraventricular tachyarrhythmias: it permits selection of optimal long-term anti-arrhythmic treatment and is well tolerated, only slightly invasive and without adverse effects.

Administration, Oral↗
PubMed1992

Life-threatening tachyarrhythmias in athletes.

The arrhythmias in competitive athletes may be classified as "benign," "paraphysiological" due to prolonged athletic training, or "pathological" due to hemodynamic effects on the athletic performance-risk-arrhythmogenic substratum. Pathological arrhythmias include life-threatening forms that are severe enough to produce symptoms (presyncope, syncope, cardiac arrest) during athletic activity. These forms are in particular rapid VT, VF, torsades de pointes, preexcited atrial fibrillation, sinus atrial and AV block. Our study population includes 766 competitive athletes, mean age 21.1 years (74 top international level), investigated with a cardioarrhythmological work-up for symptoms and for arrhythmias from 1974 to June 30, 1991. Three leading categories, represented by 16 aborted sudden death, 8 sudden death, and 7 induced VF (by EES or TAP) athletes, are described. All athletes with life-threatening arrhythmias, previously as asymptomatic or with minor symptoms had an arrhythmogenic substratum due to underlying silent cardiopathy or primary arrhythmic disorders. Athletic activity can be regarded as a trigger of electrical destabilization.

Adolescent↗
PubMed1992

[Sotalol in the Wolff-Parkinson-White syndrome: an electrophysiological and clinical study].

Distinctly different from the other beta-blocking agents, sotalol prolongs action potential duration in myocardial and Purkinje fibers, and increases atrial as well as ventricular effective refractory periods. Similarly, antegrade and retrograde accessory pathway refractory periods are increased by sotalol. The electrophysiologic and clinical effects of sotalol were studied in 40 patients (31 male and 9 female, mean age 32 +/- 14 years) with Wolff-Parkinson-White Syndrome (WPW). All patients had disabling episodes of supraventricular tachyarrhythmias (ST). Of the 40 patients, 15 (37%) had spontaneous recurrence of paroxysmal supraventricular reciprocating tachycardia (PSRT), 14 (35%) of atrial fibrillation (AF) and 11 (28%) of both PSRT and AF. All of the patients were non responders to serial transesophageal electropharmacological tests using I C class drugs. Sotalol 252 +/- 73 mg daily was administered, and, in steady-state, a new transesophageal study (TS) was performed to observe the re-induction of PSRT and/or AF. 34 patients (85%) were responders to TS (noninducibility of ST, or nonsustained ST or AF inducibility with an increase of 30% in the minimum R-R interval between pre-excitated beats during AF) and the results were confirmed during a follow-up of 17 +/- 9 months. In the non-responder group (5 patients), a I C class drug was associated with sotalol. One patient, who was a "non responder" to sotalol, sotalol + I C class drug, and to amiodarone, underwent surgical therapy. In the 26 patients (65%) who had episodes of PSRT (37%) or episodes of PSRT and AF (28%), it was impossible to reinduce PSRT in 85% of the cases. AF was induced at baseline in all of the studied patients, but after sotalol administration in 15 patients, it was impossible to reinduce AF. The rate of induced AF decreased from 208 +/- 39 beats/min to 156 +/- 36 beats/min (p < 0.001). The mean shortest R-R interval between pre-excitated beats increased from 214 +/- 35 (baseline) to 293 +/- 97 msec (sotalol steady state) (p < 0.001). No side effects were observed. A significant prolongation (p < 0.001) of the QTc interval was observed in all the patients after sotalol administration (from 0.39 +/- 0.2 to 0.42 +/- 0.02 sec.). On the basis of our results, we may conclude that sotalol has a potent effect on the antegrade refractoriness of the anomalous pathway and, in WPW syndrome at risk, is also effective in patients who don't respond to I C class drugs.

Adult↗
PubMed1992

[Vascular lesions in Candida albicans sepsis].

In two premature newborns affected by candida sepsis we observed at ultrasonography alterations of the heart and of the anterior cerebral artery. These alterations suggest a cardiovascular involvement that is rarely reported in the literature as a complication of systemic candidiasis.

Candidiasis↗