P1450Deep vein thrombosis after right sided catheter ablation; more common then previously thought?

Funding Acknowledgements

Bristol-Myers Squibb

Background

Right sided cardiac catheter ablation has become an indispensable tool to treat supraventricular cardiac dysrhythmias, with ablation of certain arrhythmias having cure rates over 90%. Due to this the frequency of these procedures is increasing annually and it is imperative we understand the incidence of all complication. One lesser studied complication is that of deep vein thrombosis (DVT), for which catheter ablation demonstrates all elements of Virchow"s triad.  As right sided ablations are carried out to treat troublesome palpitations, not to reduce mortality, it is important all risks are identified, especially those which are themselves potentially life threatening and can be modified.

Purpose

 

To determine the incidence of DVT after right sided cardiac catheter ablation.

Methods

 

We undertook a prospective multi-center study recruiting adult patients undergoing clinically indicated cardiac ablation for atrioventricular nodal re-entrant tachycardia and atrioventricular re-entrant tachycardia with right sided accessory pathway. Important exclusion criteria included patients on anticoagulation or antiplatelet therapy. Participants underwent bilateral compression venous duplex ultrasonography from the inferior vena cava to the popliteal vein to access for DVT at 24 hours and between 10 to 14 days post-procedure. The uncannulated contralateral leg acted as a control.

Result

 

At interim analysis 71 participants had completed the study with average age 47 year (+/- 14), procedure duration 67 minutes, and with a female predominance. Seven patients developed acute DVT in either the femoral or internal iliac vein in the access leg. No thrombus was seen in the control leg. This gives an incidence of 10% (95% CI 4-19%) with p value of 0.023 on Chi-square testing.

Conclusion

We found a statistically significant proportion of patients undergoing right sided cardiac catheter ablation developed acute proximal DVT on ultrasound. All patients were treated with 3 to 6 months of anticoagulation therapy in accordance with NICE guidelines. These results suggest that DVT may occur at a high frequency then previously thought in this cohort and supports the consideration of peri-procedural prophylactic anticoagulation.

Abstract Figure. Acute thrombus in the femoral vein

Haemorrhagic cerebral air embolism from an atrio-oesophageal fistula following atrial fibrillation ablation

We report the case of a man found unconscious three weeks following atrial fibrillation (AF) ablation. Cranial and thoracic imaging demonstrated multiple areas of pneumo-embolic infarction secondary to an atrio-oesophageal fistula (AEF). AEF is a recognised, but rare, complication of AF ablation.(1-8) Early recognition is critical as the mortality is 100% without surgical intervention. We consider the postulated mechanisms of AEF formation, the spectrum of clinical presentation, investigations and treatment.

Automated analysis of atrial late gadolinium enhancement imaging that correlates with endocardial voltage and clinical outcomes: a 2-center study

BACKGROUND

For late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) assessment of atrial scar to guide management and targeting of ablation in atrial fibrillation (AF), an objective, reproducible method of identifying atrial scar is required.

OBJECTIVE

To describe an automated method for operator-independent quantification of LGE that correlates with colocated endocardial voltage and clinical outcomes.

METHODS

LGE CMR imaging was performed at 2 centers, before and 3 months after pulmonary vein isolation for paroxysmal AF (n = 50). A left atrial (LA) surface scar map was constructed by using automated software, expressing intensity as multiples of standard deviation (SD) above blood pool mean. Twenty-one patients underwent endocardial voltage mapping at the time of pulmonary vein isolation (11 were redo procedures). Scar maps and voltage maps were spatially registered to the same magnetic resonance angiography (MRA) segmentation.

RESULTS

The LGE levels of 3, 4, and 5SDs above blood pool mean were associated with progressively lower bipolar voltages compared to the preceding enhancement level (0.85 ± 0.33, 0.50 ± 0.22, and 0.38 ± 0.28 mV; P = .002, P < .001, and P = .048, respectively). The proportion of atrial surface area classified as scar (ie, >3 SD above blood pool mean) on preablation scans was greater in patients with postablation AF recurrence than those without recurrence (6.6% ± 6.7% vs 3.5% ± 3.0%, P = .032). The LA volume >102 mL was associated with a significantly greater proportion of LA scar (6.4% ± 5.9% vs 3.4% ± 2.2%; P = .007).

CONCLUSIONS

LA scar quantified automatically by a simple objective method correlates with colocated endocardial voltage. Greater preablation scar is associated with LA dilatation and AF recurrence.

Use of Ivabradine in Postural Orthostatic Tachycardia Syndrome

Postural orthostatic tachycardia syndrome (POTS) is characterized by inappropriate increase in heart rate on assuming upright position from a supine position without a necessary drop in blood pressure. Etiology of this condition is complex and multifactorial. Autonomic dysfunction,[1] hypovolemia,[2] hyper responsiveness of beta adrenergic receptors[3] with associated elevations of plasma norepinephrine levels have been implicated as underlying pathophysiologic mechanisms. Beta blockers have previously been used to treat this condition. Ivabradine which selectively inhibits If ion current in the sino atrial node, has been reported to be useful in patients with POTS.[4,5] We present one further such case of POTS successfully treated by Ivabradine.