Monitoring for Complications in the First Months After AF Ablation
AF ablation is an invasive procedure that entails risks, most of which are present during the acute procedural period. However, complications can also occur in the weeks or months following ablation.920,921,922 Recognizing common symptoms after AF ablation and distinguishing those that require urgent evaluation and referral to an electrophysiologist is an important part of follow-up after AF ablation. Symptoms and complications can be divided into those that occur immediately after ablation (0–3 days), early (1–4 weeks), and those that can occur late (>4 weeks) after ablation.

Signs and Symptoms of Complications Within 1 Month Postablation
Shown in Table 5 is a list of signs and symptoms that can occur within the first several months following ablation. These signs and symptoms are divided into those that occur within 30 days of AF ablation and those that occur more than 30 days postablation. Some complications, such as a stroke or development of an AEF, might present within the first month or following the first postablation month and therefore are listed in both sections of this table. The differential diagnosis, which should be considered, as well as the recommended evaluation, are also shown. AF ablation is often performed under general anesthesia. Some patients might feel fatigued for several days after prolonged general anesthesia. Mechanical complications from endotracheal intubation and transesophageal echocardiography, such as hoarseness and difficulties swallowing, might also occur and typically resolve with time.
Tenderness at the vascular access sites is common; hematomas present after sheath removal will typically extend inferiorly (due to gravity) and might result in extensive ecchymosis after ablation. Prompt ultrasound Doppler investigation should be performed if an AV fistula or pseudoaneurysm is suspected. Worsening of back or buttock pain is also common from prolonged supine positioning during the procedure. However, more severe back pain or flank ecchymosis should prompt an evaluation for retroperitoneal hematoma with CT imaging. Significant bleeding into the leg can also result in compartment syndrome.
Shortness of breath soon after ablation might have several causes. The patient should be examined after ablation for evidence of volume overload related to irrigated ablation and diuresed as necessary. Volume overload can be observed in patients with normal or reduced cardiac function, perhaps due to atrial stunning. If dyspnea persists or occurs in the absence of volume overload, a chest X-ray should be obtained to exclude an infectious process or elevation of the respective hemi-diaphragm. PN injury most commonly occurs after balloon-based ablation, but can also occur after RF ablation.503 Lack of diaphragmatic movement during inspiration under fluoroscopy (the sniff test) is diagnostic of PN injury. Right PN injury is much more common after AF ablation and is due to ablation near the RSPV or SVC (Figure 1). Left PN injury less commonly occurs when ablating near the LAA. Although most cases of phrenic injury recover with reinnervation over a 6–12 month period after ablation, permanent diaphragmatic paralysis has been reported.
Chest pain is common after ablation; the causes include pericarditis, coronary ischemia, and musculoskeletal pain. Symptoms of pericarditis (pleuritic chest pain) are the most common (>75% of patients) and typically persist for up to a week postablation. In the absence of evidence of hemodynamic compromise, an ECG is of little value. It is important to recognize that nearly all patients will demonstrate a small pericardial effusion following AF ablation as a result of edema. Nonsteroidal anti-inflammatory agents are recommended for symptom control. Colchicine can also be used to treat pericardial symptoms. Oral steroids should be avoided after catheter ablation unless pericardial symptoms persist or are recurrent. Chest pain that is associated with ECG changes or that occurs with exertion should prompt evaluation of coronary ischemia. In particular, if ablation has been performed inside the CS to target the epicardial portion of the mitral isthmus, or for isolation of a CS tachycardia, circumflex artery stenosis should be considered.923
Any unexplained hypotension during or following ablation should be evaluated promptly. Transthoracic echocardiography or ICE (if during ablation) should be performed urgently to exclude pericardial effusion or cardiac tamponade. A complete blood count should be performed to exclude bleeding or infection.
Fever might occur early after ablation. We should exclude infectious sources such as a urinary tract infection related to bladder instrumentation or pneumonia related to intubation. Low-grade fever might also be related to pericarditis. In addition, fever might be the first marker of an impending AEF formation. Chest imaging should be considered if fever persists, an AEF is suspected, and no other clear infectious source is identified.
Any neurological symptoms occurring shortly after ablation should be taken seriously, with brain imaging performed to exclude an embolic event. Migraine-like signs and symptoms have been reported and are most commonly benign and are attributed to the residual ASD following transseptal puncture. As noted above, an AEF might also present with neurological symptoms. It is also important to recognize that an AEF might present as a neurological event and therefore must be considered the differential diagnosis of neurological symptoms that develop post AF ablation.
Symptoms of pericarditis typically persist up to a week after ablation (Table 5). If symptoms persist for >1 week or are associated with lightheadedness or shortness of breath, further evaluation is warranted. Groin pain that persists past 7 days or is getting worse should prompt a physical exam and vascular ultrasound to exclude femoral access complications. A persistent nagging dry cough might also be observed for up to 6 weeks after ablation. This complication is more common with CB than with RF ablation and is likely related to direct bronchial or lung injury. This type of cough is generally treated with antitussives and will typically subside over 4–6 weeks.
Some patients, particularly those with a history of migraines, might experience migraine headaches in the first few weeks after ablation.924,925 These headaches might be related to the residual ASD present after transseptal puncture and will typically improve over several weeks. Hemoptysis is rare but might result from pneumonia or pulmonary infarction due to an occluded PV, typically occurring 3–6 months after ablation. Dysphagia in the first days after ablation is most likely related to irritation from transesophageal echocardiography or intubation. If dysphagia persists, then imaging (chest CT or MRI) should be performed to exclude an AEF (see late complications). The differential diagnosis of dyspnea occurring early after ablation should include volume overload, pneumonia, or PN injury as outlined above. A chest roentgenogram should be obtained. If symptoms persist with a normal chest roentgenogram, we should also consider PV stenosis (see late symptoms, below). Vagal denervation of the esophagus or stomach can occur after ablation due to ablation lesions placed in the vicinity of the esophagus, particularly if extensive ablation is performed along the LA posterior wall.536,926 Symptoms can include nausea and early satiety. Patients should be advised to eat small, frequent meals. Symptoms will typically improve over 4–6 weeks. If symptoms are profound or persist, a gastric emptying study can be diagnostic. Pain at the site of sheath insertion can result from an pseudoaneurysm, an AV fistula, or a hematoma. Evaluation usually starts with a vascular ultrasound. Bloodwork and a CT scan might be appropriate.

Signs and Symptoms of Complications More Than a Month Postablation
Late symptoms of dysphagia and/or fever, particularly in the presence gastrointestinal bleeding or any neurological symptoms, should prompt an urgent evaluation for an AEF, a rare but potentially lethal complication after AF ablation (see Section 10).341,417,866,910 If AEF is suspected, esophagogastroduodenoscopy should not be performed, because increased pressure in the esophagus can lead to the introduction of air into the LA and stroke. Imaging with CT or MR is preferred, with the presence of air in the mediastinum or LA considered diagnostic. Although barium should not be introduced into the esophagus, a small amount of water-soluble contrast can help identify the location of the fistula. The recommended treatment for AEF at any stage is surgical exploration and resection of the fistulae, typically requiring resection of the involved esophagus and repair of the posterior LA wall with a pericardial patch. There have been reports of treatment of early fistulae with covered esophageal stents; however, surgical treatment is generally preferred. A persistent cough >6 weeks after ablation, particularly if associated with atypical chest pain, recurrent pneumonia or hemoptysis, should prompt an evaluation for PV stenosis.927,928 A chest roentgenogram might also show evidence of atelectasis or infiltrate localized to one lobe of the lung, which is typically related to focal pulmonary edema. Many patients have received repeated courses of antibiotics for lung infection before the correct diagnosis is reached. If PV stenosis is suspected, a chest contrast CT angiogram or MR angiogram should be performed to examine PV anatomy and exclude PV stenosis or occlusion. If PV stenosis or occlusion is detected, a ventilation or perfusion scan is typically performed to quantify lung perfusion. Referral to a center with expertise in PV stenting should be recommended early in the course of PV stenosis, because dilatation is more difficult and has a higher incidence of pulmonary hypertension, lung infarct, and hemoptysis once high grade stenosis has occurred (see Section 10: Complications). Hemoptysis should trigger an evaluation for PV stenosis and usually indicates the presence of complete branch or PV occlusion. Other late complications include a stroke or embolic event related to recurrent AF or deep vein thrombosis or pulmonary embolus related to femoral vein instrumentation. These complications are uncommon because anticoagulation is typically reinstated after ablation.