C41 AN UNUSUAL CASE OF “PULMONARY EMBOLISM”

Background

Pulmonary vein stenosis (PVS) is a complication of catheter–based radiofrequency ablation (RFA) for atrial fibrillation (AF), caused by a vascular response which leads to replacement of necrotic myocardium with collagen. Clinical presentation can mimic pulmonary embolism (PE) and usually appears some months after procedure.

Case report

A 65–year–old man was hospitalized in March 2021 with a complaint of worsening dyspnoea on exertion, over the course of one month. He had a past medical history of persistent atrial fibrillation, because of which he underwent four pulmonary vein ablations (both RFA and crioablation), the last one in 2019. The previous echocardiogram showed a high systolic pulmonary arterial pressure (sPAP of 75 + 5 mmHg) with normal right ventricular function and dimensions. Despite D–dimer at admission was negative, a CT pulmonary angiography was performed and showed occlusion of left superior pulmonary vein and a severe stenosis of right superior pulmonary vein; ventilation–perfusion scintigraphy (V/Q scan) demonstrated widespread decreased perfusion of both superior lung lobes. The patient underwent angioplasty of right pulmonary vein and after the procedure sPAP greatly decreased (35 mmHg).

Discussion

Despite its reduction in incidence and its short–term presentation from procedure, severe symptomatic pulmonary vein stenosis must be considered among complications of ablation for atrial fibrillation. Delayed symptoms can also present years after procedure, even if in literature few similar cases are described. Ventilation–perfusion scintigraphy is a very sensible method to assess the functional significance of pulmonary vein stenosis and it also relates with symptoms’ severity. It should be performed in case of a high clinical suspicion, considering that the characteristic ventilation–perfusion mismatch of this condition can be seen in other diseases too, over all pulmonary embolism.

Conclusions

This case report emphasizes the importance of a thorough anamnesis and an exact interpretation of diagnostic imaging to correctly identify this AF ablation complication and optimize the patient’s therapeutic management. It must be considered that PV stenosis can develop late and with unusual symptoms, mimicking other diseases, like pulmonary embolism, which has the same scintigraphic imaging.

P1482 Surviving free wall rupture

Conclusion

This is a very rare case of covered free wall rupture, treated 6 months after the acute event. Multimodality imaging was essential to confirm the diagnosis and to guide the following management.

Abstract P1482 Figure 1

Evidence of parasympathetic impairment in some patients with cardiac syndrome X

OBJECTIVES

Cardiac syndrome X (SX) is a clinical condition characterised by angina, positive exercise stress test and negative coronary angiography; it has often been attributed to sympathetic hyperactivity. Here we tested the hypothesis that a parasympathetic, rather than a sympathetic, dysfunction could be the cause of the autonomic imbalance observed in SX.

METHODS

In 20 subjects with diagnosed SX and in 12 age-matched controls, we studied autonomic function by performing spectral analysis of RR interval and finger arterial pressure (SAP), in supine position and during head-up tilting. We also carried out a set of tests of parasympathetic function.

RESULTS

The group of SX patients did not differ significantly from control subjects in any of the variables tested. In a subgroup of 13 SX, however, tilting increased the low-frequency power of SAP, but did not induce the expected increase in low-frequency and decrease in high-frequency power of RR. These patients, in supine position, had significantly lower sinus arrhythmia and a higher ratio of low to high frequency of RR, in comparison with control subjects. We interpreted these differences as signs of reduced parasympathetic, but essentially normal sympathetic, activity. The parasympathetic tests confirmed vagal impairment in the same SX subjects. On the other hand, all the tests indicated normal parasympathetic functions in the control subjects and in those SX patients who displayed the expected spectral changes in tilting.

CONCLUSIONS

In about two thirds of the patients with SX, the pathophysiological mechanism causing the symptoms could be related to the reduced parasympathetic tone, rather than to an augmented sympathetic activity.

Coronary artery vasomotion and post-stenotic coronary artery blood flow after intracoronary lacidipine in patients with ischaemic heart disease: a pilot study

BACKGROUND

The calcium antagonist lacidipine has been shown to be highly vasoselective and to improve myocardial perfusion in hypertensive patients. However, its effects on coronary artery vasomotility and on post-stenotic coronary flow reserve in patients with atherosclerotic heart disease are unknown.

OBJECTIVES

This study was designed to investigate the acute direct effects of repeated infusions of lacidipine on epicardial coronary artery vasomotion and on post-stenotic coronary artery blood flow in patients with stable angina pectoris and angiographic evidence of coronary heart disease.

METHODS

In 8 patients with stable angina and moderate to severe stenosis of the left coronary artery, measurements of epicardial dimensions (quantitative angiography) and of coronary blood flow (Doppler guidewire) distal to a stenosis were performed at baseline and after 3 repeated intracoronary boluses of 12 microg of lacidipine. Results were compared with those obtained after 10 mg of intracoronary papaverine.

RESULTS

The intracoronary administration of lacidipine was well tolerated, without any adverse effects. Lacidipine significantly increased the minimal luminal diameter of the lesion (peak relative increase of 43.7%), without significant changes in heart rate and systolic aortic pressure. Intracoronary lacidipine caused a dose-dependent increase in coronary flow reserve. Maximal vasodilatory effects were equivalent to those obtained with intracoronary papaverine.

CONCLUSIONS

These results suggest that lacidipine acts directly as a potent vasodilator in stenotic epicardial vessels and improves myocardial perfusion distal to a moderately severe stenosis in patients with stable angina.