Clinical observation of paroxysmal atrioventricular reciprocal tachycardia in intermittent Wolff–Parkinson–White syndrome

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Paroxysmal atrioventricular reciprocal tachycardia (AVRT) develops in patients with existing accessory pathways for conduction of excitation impulse between atria and ventricles. Normally excitation is conducted through the atrioventricular node and His-Purkinje system. A congenital anomaly in the form of existence of a muscular bundle between atria and ventricles that is the basis for the phenomenon of pre-excitation of ventricles and functions as an accessory conduction pathway (ACP) for the impulse. The accessory pathway may have different localizations that is confirmed by invasive (epicardial and endocardial) or body surface electrocardiographic mapping [1-3].

Attempts to find electrocardiographic criteria for determination of localization of an accessory pathway were many times undertaken by researches [2-5]. The key element of all the described schemes is determination of the direction of delta wave vector (first 20-40 ms of the ventricular complex). Along with the signs of F. Rosenbaum, et al. (1945) permitting to identify only the left and right bundles, other criteria were proposed by O.A. Obel and A.J. Camm (1998) that permitted to identify 9 variants of localization of an accessory pathway [6, 7]. L.A. Bokeria and A.Sh. Revishvili (1999) elaborated the most comprehensive scheme for topical diagnostics of the pre-excitation region in children and described12 variants of it [8].

The incidence of ACP in the total population is 0.1-0.3% cases and is twice as common in males [9, 10]. About 70% of patients with pre-excitation syndrome have no organic pathology of the heart [9]. Up to 15% of patients with pre-excitation syndrome have multiple ACPs [6].

The second most common supraventricular paroxysmal tachycardia after atrioventricular nodular tachycardia is AVRT with participation of ACP. It accounts for 80% of all arrhythmias in Wolff-Parkinson-White (WPW) syndrome [12, 13]. As a rule, the onset of paroxysmal AVRT occurs in individuals under 40 years of age [14].

In most patients with the syndrome of pre-excitation of ventricles, the anterograde refractory period of an ACP is longer than of the conduction system, and if supraventricular extra systole which gives a start to tachycardia, comes to ACP when it is in refractory period, it is conducted to ventricles through the AV node, and in the retrograde direction – through ACP. In this case a paroxysm of orthodromic AVRT is triggered (85-90% of all paroxysmal reciprocal tachycardia in syndrome of pre-excitation of ventricles). Much less common is antidromic tachycardia when excitation impulse travels anterograde via an ACP and retrograde – via the atrioventricular node. In this case tachycardia is recorded with wide ventricular complexes [15].

Clinical Case. Patient R., 41 years old, was delivered to hospital ER (Ryazan) by ambulance team (AT) with complains of a sudden attack of palpitation accompanied by discomfort in the chest. The palpitation attack developed in the usual working conditions without provoking psychoemotional and physical factors. Until the moment of delivery to hospital the patient did not consider himself ill and had no cardiologic anamnesis. The AT recorded supraventricular tachycardia in the ECG with heart rate (HR) 150 beats per minute. The patient was hospitalized to the cardiologic department.

On examination the general condition corresponded to severity of the disease. The patient was excited, emotionally labile. Skin of usual color and moistness. Normo-sthenic build, supernutrition, height 174 cm, weight 82 kg, body mass index (BMI) 27.2 kg/m².Over lungs vesicular breathing, no crackles, respiratory rate 20 per minute. The borders of deep cardiac dullness not expanded. In auscultation, heart sounds of sufficient sonority, regular rhythm. HR 150 beat/min, arterial pressure 140 and 94 mm Hg. The abdomen soft, painless to palpation, the lower edge of the liver is determined by the level of the costal margin. No peripheral edema.

In the ECG tachycardia was recorded with narrow ventricular complexes with HR 150 beat/min, absence of P waves,probably from the atrioventricular node, normal orien-tation of the electrical axis of the heart (Figure 1).

In 10 minutes after intravenous slow introduction of propanorm solution at a dose 123 mg (at the rate of 1.5 mg/kg), sinus rhythm was recorded in the ECG. The patient felt better.

In the ECG in dynamics sinus rhythm was recorded, intermittent WPW phenomenon (Figure 2).

 

Fig. 1. ECG on delivery

 

Fig. 2. ECG in dynamics

 

In the given ECG (Figure 2), a shortened PO interval, delta wave, widened ventricular complex with disorders in repolarization processes were recorded in the 1^st and 5^th complexes. The presence of positive QRS complex in a VL and V1 leads suggests the existence of ACP of the left posterolateral localization.

The results of echocardiography: the aorta of normal dimension, 20-35 mm, a mild enlargement of the left atrium (41*50 mm), left ventricle of normal size (the end-diastolic dimension 47 mm, the end-systolic dimension 29 mm), the right atrium not enlarged (33*42 mm), the right ventricle of normal dimension. Ejection fraction of LV 66% (norm). Disorder in the function of relaxation of the left ventricle: VA>VE, the time of isovolumic relaxation (IVRT) 0.11 s. 1-2 Degree mitral regurgitation, 1 degree tricuspid regurgitation. Conclusionon echocardiography: mild enlargement of the left atrium. Disorders in the diastolic function of the LV of the 1 type. Moderate regurgitation of the mitral valve. Mild regurgitation of the tricuspid valve.

Common blood count and common urine test: with no pathology. Biochemical blood test: total protein: 65 g/L, AST 19 Un/L, ALT 22 Un/L, creatinine 97 µmol/L (glomerular filtration rate 83 mL/min*1.73 m²), glucose 5.6 mmol/L, total cholesterol 5.6 mmol/L, high density lipoproteins 1.4 mmol/L, low density lipoproteins 3.2 mmol/L, triglycerides 0.8 mmol/L.

Differential diagnosis with atrioventricular nodular tachycardia was conducted. Existence of paroxysm of tachycardia with narrow ventricular complexes without P wave and the phenomenon of pre-excitation of ventricles with sinus rhythm in subsequent ECGs permitted to diagnose paroxysmal AVRT with intermittent Wolff-Parkinson-White syndrome. Taking into account the late onset of arrhythmia, absence of unfavorable cardiologic anamnesis and of organic pathology of the heart, it was decided not to resort to prophylactic antiarrhythmic therapy leaving the patient for dynamic outpatient observation.

Taking into account repeated episodes of elevation of the arterial pressure above 140 and 90 mm Hg, echocardiography data (1 type diastolic dysfunction of the left ventricle and moderate enlargement of the left atrium), the patient was administered hypotensive monotherapy with a preparation of the group of angiotensin converting enzyme (ACE) inhibitor. Measures were recommended to reduce the body mass to achieve the normal BMI, also systematic control of the arterial pressure, 24-hour monitoring of the arterial pressure for assessment of the effectiveness of the conducted therapeutic measures.

Conclusion

The given clinical case of patient R., 41 years old, demonstrated that a widely available examination method – electrocardiography – permits to determine the character of arrhythmia, to choose treatment tactics, to evaluate the prognosis for the disease before administration of complicated invasive manipulations.

About the authors

Natalya P. Pavlova

Ryazan State Medical University

Author for correspondence.
Email: natusik.ryazan@mail.ru
ORCID iD: 0000-0003-1545-7313
SPIN-code: 9310-9159

MD, PhD, Associate Professor of the Department of Faculty Therapy with the Therapy Course of the Additional Postgraduate Education Faculty

Russian Federation, Ryazan

Nina M. Artemova

Ryazan State Medical University

Email: natusik.ryazan@mail.ru
ORCID iD: 0000-0002-6170-3442
SPIN-code: 7814-0284

MD, PhD, Associate Professor of the Department of Faculty Therapy with the Therapy Course of the Additional Postgraduate Education Faculty

Russian Federation, Ryazan

Elena A. Maksimtseva

Ryazan State Medical University

Email: natusik.ryazan@mail.ru
ORCID iD: 0000-0003-3528-6398
SPIN-code: 5505-4415

MD, PhD, Associate Professor of the Department of Faculty Therapy with the Therapy Course of the Additional Postgraduate Education Faculty

Russian Federation, Ryazan

Oleg M. Uryasiev

Ryazan State Medical University

Email: natusik.ryazan@mail.ru
ORCID iD: 0000-0001-8693-4696
SPIN-code: 7903-4609
ResearcherId: S-6270-2016

MD, PhD, Professor, Head of the Department of Faculty Therapy with the Therapy Course of the Additional Postgraduate Education Faculty

Russian Federation, Ryazan

References

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