Catheter Ablation Without Fulguration: Design and Performance of a New System

A new system is described for catheter ablation which comprises a short time capacitive power source and a specially designed catheter. The aim of the new system is to deliver high voltages with minimal or no arcing and thus avoid the risks associated with barotrauma. The performance of the new system was compared in a saline tank with that of the conventional system. The new system allowed significant increases in delivered voltage, current and energy without arcing. This new system should allow safer catheter ablation.     

The Usefulness of a Stretch-Polyester Pouch to Encase Implanted Pacemakers and Defibrillators

This study was undertaken to assess the effects of enclosing permanent pacemaker and ICD pulse generators in a stretch-polyester pouch prior to implantation. Follow-up of 223 patients with oversized pacemakers and with ICDs and 344 witb standard-sized pacemaker pulse generators showed that the pouch was effective in decreasing the frequency of pulse generator migration and extrusion.     

Toxic Porphyria

1. Numerous cases of porphyria of the "cutanea tarda" type were observedrecently in the southeastern districts of Turkey. The toxic agents appearto have been fungicides, including two mercury compounds together withhexachlorobenzol which were added to seed wheat. The disease did notappear in peasants who did not consume this seed wheat. There were noindications of buckwheat toxicity; furthermore, this seed is not cultivatedin Turkey.

Six of the affected patients were treated in our clinic.

2. Clinically the patients presented cachexia, bullae, hyperpigmentationand hypertrichosis, i.e., skin lesions of the cutanea tarda type of porphyria.There were no cases of splenomegaly, and no abdominal or neurologic signs.

3. The patients were found to have an organic and functional liver disease.No suprarenal cortical dysfunction was recorded. X-rays of the bones werenormal. No signs of hemolysis were present. Bone marrow studies revealedslight normoblastic hyperplasia.

4. Urinary porphobilinogen was repeatedly found to be negative. Urinaryand fecal uroporphyrin 1 and coproporphyin 111 were present in excess. Thefecal excretion of coproporphyrin 111 was greater than that of uroporphyrin1, whereas in the urine the relation was reversed. The bone marrow contentof porphyrin was not increased. No fluorescence was recorded in the freshunstained blood smears by fluorescence microscopy.

5. Our cases had the clinical and laboratory findings consistent with thecutanea tarda type of porphyria.

6. The advanced and severe alteration of our patients' porphyrin metabolismmay not be reversible. Although the bullae disappeared during their hospitalresidence, the excessive porphyrin excretion was still present on theirdeparture from the clinic.

7. For therapy, the patients were given a high caloric diet of protein richfood and treated with liver extracts, vitamin B₁, B₂, B₁₂ and whole B-complexpreparations. We can express no opinion as to the value of this treatment.

Submitted on September 13, 1959 Accepted on February 12, 1960     

Correlation of Spontaneous and Induced Premature Atrial Complexes Initiating Atrial Fibrillation in Humans: Electrophysiologic Parameters for Guiding Therapy

INTRODUCTION: The low frequency of spontaneous premature atrial contractions (PACs) may be an impediment to mapping and ablation of atrial fibrillation (AF). It has been shown that PACs following external or internal cardioversion of AF can initiate AF. If this method could reproducibly induce PACs from the same location as spontaneous PACs, it would be clinically significant. High-resolution noncontact mapping can map a single beat, should help identify the sites of spontaneously occurring PACs and PACs induced following cardioversion of spontaneous or induced AF, and could help correlate the trigger sites for AF induction. METHODS AND RESULTS: Twelve patients (8 men and 4 women; mean age 49+/-10 years) with spontaneous PACs were included in the study. In all patients, AF was induced and subsequently cardioverted to assess and map isolated PACs or PACs that induced AF. Using the EnSite 3000 noncontact mapping system, mapping was performed of spontaneously occurring isolated PACs and PACs that induced AF and PACs (both with and without AF) that occurred on at least two different occasions following cardioversion. The locations of the spontaneous and the induced PACs were similar; 97% of induced PACs came from the same locations as those of spontaneous PACs (P = 0.5). Radiofrequency lesions guided by this mapping technique were delivered at 14 pulmonary vein sites. Following a single ablation attempt during a mean follow-up of 19+/-4 weeks, 42% of the patients were in sinus rhythm and drug-free, whereas an additional 24% of patients could be maintained in sinus rhythm on drugs that had failed before. CONCLUSION: There is a high degree of correlation between spontaneous and induced PACs as the trigger sites for AF initiation. Cardioversion of spontaneous or induced AF could be used as an electrophysiologic parameter for guiding therapy.     

A diagnosis not to be missed: Behcet’s disease as a cause of dilated cardiomyopathy in a young Arab male patient

We report a 33‐year‐old Arab male patient who was thought to have severe idiopathic dilated cardiomyopathy (DCM) associated with complete atrioventricular block for more than 6 years, then was found to possess features suggestive of underlying Behcet’s disease in the form of recurrent oral and genital ulcers, cutaneous folliculitis, superficial thrombophlebitis, pathergism, partially thrombosed portal vein and a positive human leukocyte antigen ‐B51.     

Intravascular leiomyomatosis and benign metastasizing leiomyoma: an unusual case

Benign metastasizing leiomyoma (BML) and intravascular leiomyomatosis (IVL) are rare variants of uterine leiomyomas. In our search of available literature, there have been only two reports of these conditions occurring in the same patient. We report a case of a 42-year-old female presenting with a left L4 nerve root lesion, left paravesical lesion, left ovarian cyst, multiple pulmonary metastases, and an intracaval lesion. Histology confirmed these to be leiomyomata strongly positive for estrogen receptors. Treatment included surgery, in two stages, to remove the L4 nerve root, left paravesical lesion, intracaval lesion, and a single pulmonary nodule. The remaining tumor was treated with a gonadotrophin-releasing hormone agonist, resulting in significant reductions in tumor size. It was concluded that the lesions in the lungs were an example of BML arising from the initial diagnosis of uterine leiomyoma, and the caval lesion was an IVL. Long-term follow-up is recommended, and familiarity with rare forms of benign smooth muscle uterine tumors is essential in avoiding misdiagnosis and overtreatment.     

Low Energy Catheter Ablation of a Posteroseptal Accessory Pathway Associated with a Diverticulum of the Coronary Sinus

A 23-year-old man was resuscitated from ventricular fibrillation and subsequently shown to have the Wolff-Parkinson-White syndrome. Electrophysiological study demonstrated a posteroseptal accessory pathway, and coronary sinus angiography demonstrated that this was associated with a diverticulum of the coronary sinus. Catheter ablation was performed using a new low energy system. Five shocks were delivered within the coronary sinus diverticulum, with a cumulative energy of 39 joules (J). Accessory pathway conduction was blocked successfully, and there were no complications.     

Impedance Changes During Catheter Ablation and Their Relationship to Electrical Arcing and Clinical Efficacy

This study has used high energy ablative shocks in saline and in man to characterize the complex, energy dependent behavior of the impedance at the electrode-tissue interface. In vitro shocks showed a fall in impedance when an arc was formed, due to formation around the electrode of a vapor globe rendered conductive by the arc. Following arc extinction, this same vapor globe insulates the electrode, and subsequently collapses, forming a shock wave, and allowing current flow to resume. Shocks delivered to tissue specimens exhibited progressively higher impedance and less insulation as contact pressure was increased. In vivo, lesser degrees of insulation during arcing shocks were associated with greater clinical efficacy.