Left ventricular hypertrophy in a young adult

A 21-year-old male was referred for investigation of complaint of chest pain associated with breathlessness duringexertion. There was no history of leg swelling, orthopnoea or paroxysmal nocturnal dyspnoea. He had no history of hypertension, family history of heart disease or sudden death. On clinical examination, he was well built. The blood pressure was normal. The pulse had a jerky nature. There was an additional fourth heart sound and a short late systolic murmur over the left sternal edge.

An accurate stepwise electrocardiographic algorithm for localization of accessory pathways in patients with Wolff-Parkinson-White syndrome from a comprehensive analysis of delta waves and R/S ratio during sinus rhythm

Prediction of accessory pathway location before radio-frequency ablation has become increasingly important for patients with Wolff-Parkinson-White syndrome. However, existing electrocardiographic (ECG) criteria for localization of accessory pathways have several limitations, and the polarity of delta waves has not been well defined. In the present study, 369 patients with a single anterogradely conducting accessory pathway who underwent successful radiofrequency ablation were included. The polarity of delta waves was defined and categorized in detail, and various ECG characteristics of the most preexcited QRS complexes were examined and compared with QRS complexes after successful ablation in the initial 182 patients, which included morphology and polarity of delta waves, initial 20, 40, and 60 ms segments of the preexcited QRS complex, R/S ratio in the precordial leads, R/S ratio in the frontal leads, delta wave axis in the frontal plane, polarity of delta waves in the frontal leads, and polarity of delta waves in the precordial leads. The polarity of the initial 40 ms segment of the most preexcited QRS complexes in each of the frontal leads, and the polarity of the initial 60 ms segment of the most preexcited QRS complex in each of the precordial leads proved to be the best representatives of delta wave polarity in the respective leads.(ABSTRACT TRUNCATED AT 250 WORDS)

Right praecordial early repolarization pattern occurring with the Wolff-Parkinson-White pattern

A 47 year old man presented with simultaneous electrocardiographic manifestation of the right praecordial early repolarization pattern and the Wolff-Parkinson-White pattern. The important features of this combined pattern and helpful clues which will enable the correct diagnosis to be made are discussed in this paper.

Upright tilt table testing in the evaluation of syncope

OBJECTIVES

To review our experience with the upright tilt table test for the diagnosis of vasovagal syncope in a group of unselected patients with a history of syncope or presyncope.

METHODS

179 patients with a history of syncope or presyncope were subjected to upright tilt test. After carotid sinus massage to exclude carotid sinus hypersensitivity, the patients were tilted on a motorised tilt table with footplate support to an angle of sixty to seventy degrees for thirty minutes. If syncope was not induced, isoprenaline was then infused for a further fifteen minutes. A positive response was defined as fulfilling at least two out of three criteria: (i) syncope or presyncope similar to the spontaneous episodes of syncope, (ii) relative slowing of the heart rate at the onset of symptoms, (iii) drop of systolic pressure to less than 90 mmHg or by more than 50 mmHg.

STATISTICAL METHODS

Continuous variables are expressed as mean values +/- one standard deviation and analysed for statistical significance by the unpaired Student's t-test. Chi-squared test with continuity correction was used for dichotomous variables.

RESULTS

Ninety-four patients (53%) were positive for vasovagal syncope. Fourteen patients (8%) were positive at baseline tilt. An additional 80 patients (45%) were positive with the use of isoprenaline. Ten percent of the positive responses were purely cardioinhibitory, 10% purely vasodepressor and 80% mixed. The commonest cardiac rhythm during a positive response was junctional rhythm (46%) followed by sinus rhythm (44%). Sinus arrest with ventricular standstill occurred in only 5%. Accelerated idioventricular rhythm, 2:1 atrioventricular block and ventricular bigeminy accounted for the remaining 5%.

CONCLUSION

The upright tilt table test is useful for the diagnosis of vasovagal syncope.

Anaesthetic management of idiopathic long QT syndrome--a case report

This report describes the management of a patient with Idiopathic Long QT Syndrome (LQTS). The patient had life-threatening ventricular arrhythmias which did not respond to drug therapy with propranolol and phenytoin. A series of left stellate ganglion blocks were performed to control the arrhythmias. After stabilisation a high left thoracic sympathectomy was performed for a more permanent control of arrhythmias. Perioperative anaesthetic management is described and the usefulness of stellate ganglion block is demonstrated.

Radiofrequency catheter ablation of accessory pathways: the initial experience in Singapore

Radiofrequency catheter ablation is a recently introduced non-surgical technique for curing patients with arrhythmias as a result of conduction over an accessory pathway in patients with the Wolff-Parkinson-White (WPW) syndrome. We present our initial experience with this technique. There were 90 patients (61 males, 29 females) with a mean age of 37 +/- 14.4 years (range: 13-73 years). All except one were symptomatic with a mean duration of symptoms of 10 +/- 9.4 years (range: 0.1-40 years). The indications for catheter ablation were failure of drug therapy in 71, patient's preference in 10, increased risk of sudden death in 6 and almost incessant tachycardia in 3. The radiofrequency ablation was performed using a deflectable 7 French 4 mm tip electrode catheter positioned at the mitral or tricuspid annulus. The site of the accessory pathway was localised by electrophysiological study and radiofrequency energy applied via the tip of the catheter. There were 100 accessory pathways as 10 (10%) patients had multiple accessory pathways. There were 69 (69%) left free wall, 11 (11%) posteroseptal, 13 (13%) right free wall, 6 (6%) right anteroseptal accessory pathways and one (1%) midseptal accessory pathways. Ninety-six percent (96%) of the accessory pathways were successfully ablated on the first ablation. Two of the 4 initially unsuccessful ablations were successfully reablated, giving an overall success rate of 98%. There were no major complications. In conclusion, radiofrequency catheter ablation of accessory pathways is highly successful and safe and provides a definitive cure for patients with the WPW syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Bundle branch block and syncope? Right bundle branch block with left anterior hemiblock and prolonged PR interval-trifascicular block

An 84-year-old Indian man was admitted with a history of recurrent episodes of giddiness for the last 5 years. He also had 3 previous episodes of transient loss of consciousness. He has a history of hypertension for the past 28 years and angina pectoris for the past 10 years. The clinical examination was unremarkable and no postural hypotension was detected. The electrocardiogram is illustrated in Fig 1.

New directions in cardiovascular mapping and therapy

Cardiovascular mapping has allowed us to fully understand the mechanisms of some of the cardiac arrhythmias and enabled us to devise new therapeutic options for them. Endocardial mapping by electrophysiological studies using three to four endocardial catheters introduced via the vein or artery to the heart allows us to directly map the electrical activity of the heart during sinus rhythm and during abnormal tachyarrhythmias. The simultaneous recording of electrical activity from the surface electrocardiogram, right ventricular apex, His bundle, high right atrium, coronary sinus, with or without a roving mapping catheter, enables us to precisely map the electrical activation sequence in the heart. This technique has been especially useful for mapping supraventricular tachycardias and the precise mapping of the accessory pathway or slow pathway potentials have now allowed us to selectively ablate them using radiofrequency energy delivered via the tip of the endocardial catheter. Intraoperative direct cardiac mapping has allowed us to reconfirm the findings of endocardial catheter mapping immediately prior to surgery. The intraoperative mapping is more precise and allows direct visualisation of the abnormal site for the surgeon to operate. Computerised mapping using multichannel recordings has facilitated mapping of the abnormal site for patients with haemodynamically unstable or nonsustained ventricular tachycardia, and thus allows the surgeon to perform surgical resection or cryoablation of the abnormal site. Cardiovascular mapping has thus enabled us not only to understand the mechanisms of cardiac arrhythmias but allows us to provide curative therapy for patients who are at risk from sudden arrhythmic death or otherwise need life long drug therapy.

A unique preexcitation pattern related to an atypical anteroseptal accessory pathway

Accessory atrioventricular pathways have traditionally been classified by anatomical location to four areas, namely anteroseptal, posteroseptal, and right and left free walls. Each of these have been associated with a relatively distinct preexicitation pattern electrocardiographically. We describe a patient with a unique ECG pattern suggesting preexicitation to the right ventricular outflow region. Preoperative and intraoperative electrophysiological testing confirmed the presence of an accessory pathway with an atrial insertion site near the His bundle, decremental anterograde conduction, and a ventricular insertion site in the upper part of the interventricular septum. Operative ablation near the atrial insertion site eliminated preexicitation.