TAVR Complications: Stroke, Pacemaker, and Leak Risks

Transcatheter aortic valve replacement (TAVR) is remarkably safe for a procedure that threads a new heart valve through your blood vessels and deploys it inside a beating heart, but it carries a distinct profile of complications that patients and families should understand before and after the procedure. The most common issues include vascular injuries at the access site, a need for a permanent pacemaker, some degree of leak around the new valve, stroke, kidney stress, and bleeding. Less common but serious risks include infection of the new valve, coronary artery blockage, and structural damage to the heart itself. Each of these complications has its own set of risk factors, timing, and outlook.

Vascular Access Injuries

Most TAVR procedures today go through the femoral artery in the groin, and the large delivery catheter can injure the artery or surrounding vessels on the way in or out. In earlier studies using older, bulkier delivery systems, major vascular complications affected roughly one in seven patients undergoing transfemoral TAVR, with female sex and larger catheter sizes serving as independent predictors of trouble.¹ With the shift to lower-profile, newer-generation valves, vascular complication rates have dropped. A study of patients receiving the SAPIEN 3 valve found that about one in five still had some form of vascular complication, but the majority were minor, with major events occurring in roughly 6% of cases. The strongest predictor of a major problem was the ratio between the catheter sheath size and the patient’s artery diameter.²

In practical terms, this means that patients with smaller arteries face higher risk, and women are disproportionately affected because their iliac and femoral arteries tend to be narrower. Pre-procedure CT imaging helps the team measure the vessels and choose an access route that minimizes the mismatch between catheter and artery. When the femoral approach looks too risky, alternative access sites such as the subclavian artery, the carotid artery, or even a direct approach through the chest wall can be used, though each carries its own trade-offs.

Stroke

Stroke is one of the most feared TAVR complications because it can permanently change a person’s quality of life. The risk is not evenly distributed over time. Roughly half of all strokes after TAVR happen within the first two days, driven by debris dislodged during the procedure itself. A second cluster occurs between days two and thirty, and a smaller portion appears in the months and years that follow.³ Early strokes are typically caused by particles of calcium or tissue knocked loose when the valve is positioned and expanded. Delayed strokes often involve blood clots forming on the new valve or in the heart, while late strokes tend to reflect the patient’s own baseline risk factors such as atrial fibrillation and frailty.⁴

Data from the PARTNER trial showed that stroke occurred in about 3.3% of patients within the first 30 days, with the vast majority happening in the first week and a pronounced peak on the second day after the procedure.⁵ Cerebral embolic protection devices, which are essentially small filters placed in the arteries leading to the brain, have been developed to catch debris during the procedure. The largest randomized trial of such a device, PROTECTED-TAVR, found that overall stroke rates were similar between the filter group and the control group (about 2.3% versus 2.9%), though disabling stroke specifically was reduced with the filter.⁶ A meta-analysis pooling data from multiple randomized trials confirmed that embolic protection devices have not significantly reduced overall stroke rates so far, though the reduction in disabling stroke with one particular device is a finding that researchers are watching closely.⁷

Needing a Permanent Pacemaker

The aortic valve sits close to the heart’s electrical conduction system, and the force of deploying a new valve can injure or compress the tissue that transmits heartbeat signals. When this happens, the heart can develop a dangerously slow rhythm or a complete block in its electrical pathway, requiring a permanent pacemaker. This is one of the most common complications after TAVR, and rates vary substantially depending on which valve design is used.

A network meta-analysis comparing three types of TAVR valves found that balloon-expandable valves had a pacemaker implantation rate of about 19%, self-expandable valves came in around 25%, and mechanically expandable valves were highest at roughly 35%.⁸ A large nationwide analysis confirmed that balloon-expandable technology carried consistently lower pacemaker risk than self-expandable designs, both in the first 30 days and over longer follow-up.⁹ The difference comes down to how each valve interacts with the surrounding anatomy: self-expanding and mechanically expanding valves exert more radial force on the conduction tissue sitting just below the aortic ring.

Whether a new pacemaker actually harms long-term outcomes is debated. Some patients do fine with a pacemaker and never think twice about it. But becoming pacemaker-dependent after TAVR can lead to issues if the heart’s own rhythm doesn’t recover, and the combination of a pacemaker plus a transcatheter valve adds a layer of complexity to future cardiac care. Patients with a pre-existing bundle branch block on their ECG are at the highest risk and should discuss this possibility thoroughly with their care team before the procedure.

Paravalvular Leak

Unlike a surgically sewn valve, a TAVR valve is crimped onto a catheter and expanded into place. If the new valve doesn’t seal perfectly against the native annulus, blood can leak backward around the outside edges. This is called paravalvular leak, or paravalvular regurgitation, and it is one of the signature concerns unique to TAVR. Some degree of leak is common. What matters is how much.

A large meta-analysis of individual patient data found that any paravalvular leak after TAVR was associated with a roughly 50% higher risk of death and an 80% higher risk of rehospitalization over time compared to no leak at all. This held true even when the leak was graded as mild.¹⁰ A Japanese registry study that followed patients for nine years confirmed that even mild paravalvular regurgitation independently predicted worse long-term survival and a higher rate of valve failure compared to patients with no or trace leak.¹¹

Patients with bicuspid aortic valves, where the valve has two leaflets instead of the normal three, face a higher risk of paravalvular leak because the irregular, often heavily calcified opening makes it harder to achieve a perfect seal.¹² That said, newer valve designs and better preprocedural CT planning have narrowed the gap. A study comparing TAVR outcomes in bicuspid versus standard tricuspid valves with heavy calcification found similar technical success rates, though bicuspid patients still had higher pacemaker rates.¹³

Leaflet Thrombosis

One of the more subtle complications after TAVR is the formation of blood clots on the valve leaflets, a finding often detected not by symptoms but by specialized CT imaging that shows thickened, sluggish-looking leaflets. In one study that performed serial CT scans, this phenomenon was absent at discharge in nearly all patients but appeared in about one in ten by six months and roughly one in seven by one year.¹⁴ Patients with leaflet thrombosis had notably elevated blood clot markers, though short-term outcomes like death and stroke were similar between those with and without it.

The clinical significance of subclinical leaflet thrombosis remains an area of active research. It may contribute to later valve deterioration or serve as a potential source of emboli that cause stroke. Detecting it reliably requires a CT scan that captures the heart throughout its entire beating cycle, which not all imaging protocols include.¹⁵ Whether all patients should undergo routine post-TAVR CT surveillance, and whether finding leaflet thrombosis should trigger anticoagulation therapy, are questions that don’t yet have definitive answers.

Kidney Injury

Acute kidney injury after TAVR is more common than many patients expect. The causes are several: the contrast dye used for imaging during the procedure, episodes of low blood pressure, and the patient’s pre-existing kidney function all play a role.¹⁶ When kidney injury does occur, it carries a serious toll. A nationwide study found that patients who developed kidney injury after TAVR faced more than double the risk of death and a sevenfold increase in the rate of needing dialysis over the following year compared to those whose kidneys remained stable.¹⁷

The encouraging finding from that same study is that among survivors, about three-quarters had complete kidney recovery within six months. Still, about one in twenty who developed kidney injury ended up on dialysis. The risk is even more ominous for patients who already have a weak heart pump combined with a narrowed valve, a condition called low-flow, low-gradient aortic stenosis, where kidney injury after TAVR carries particularly severe prognostic implications.¹⁸ For patients with borderline kidney function before TAVR, the procedure team typically minimizes contrast use and ensures aggressive hydration to protect the kidneys.

Endocarditis

Infection of the replacement valve, known as endocarditis, is uncommon but devastating when it occurs. A study of nearly 135,000 TAVR patients in the United States found that about 1.4% developed endocarditis, with the annual incidence running at just under 1% per year. More than half of these infections appeared between one month and one year after the procedure, and the most common bacteria identified were Staphylococcus, Streptococcus, and Enterococcus species.¹⁹

The consequences are grim. One-year mortality among those who developed endocarditis was nearly 46%, and after adjusting for other health factors, endocarditis was associated with roughly a threefold higher risk of death compared to patients who stayed infection-free. Despite improvements in TAVR technique and the trend toward treating younger, healthier patients, the incidence of endocarditis has remained stubbornly stable and appears similar to rates seen after traditional surgical valve replacement.²⁰ This makes good dental hygiene, careful attention to skin wounds, and prompt treatment of infections especially important for anyone living with a TAVR valve.

Coronary Artery Obstruction

When the TAVR valve is deployed, the native valve leaflets are pushed outward. In rare cases, a displaced leaflet can block the opening of a coronary artery, cutting off blood flow to the heart muscle. This is an uncommon but life-threatening emergency. Pre-procedure CT imaging has become central to predicting who is at risk. A validated multivariate model that accounts for the height of the native valve cusp relative to the coronary opening, the expected distance between the deployed valve and the coronary artery, and the volume of calcium on the leaflet performs well, with diagnostic accuracy above 90% for predicting obstruction of either the left or right coronary artery.²¹

When the anatomy looks risky, operators can plan protective strategies in advance, such as placing a wire or stent in the coronary artery before the valve is deployed so that blood flow can be restored immediately if blockage occurs. For patients undergoing a valve-in-valve procedure, where a new TAVR valve is placed inside a failing older one, the risk of coronary obstruction is higher because the prior valve’s frame further restricts space. Newer techniques including intentional splitting of the old valve leaflets have been developed to address this scenario.²²

Bleeding and Blood Thinners After TAVR

Deciding what blood-thinning medication to use after TAVR is a balancing act between preventing clots on the new valve and avoiding bleeding. For patients who don’t already need anticoagulation for another reason, the standard approach has been dual antiplatelet therapy, typically aspirin plus clopidogrel, for three to six months. However, trial evidence has increasingly suggested that this dual regimen raises bleeding risk without clearly preventing more clots or strokes, and single antiplatelet therapy with aspirin alone appears to be a reasonable alternative.²³ ²⁴

For patients who are already on oral anticoagulation, typically because of atrial fibrillation, adding an antiplatelet drug on top increases bleeding further. The general trend in practice is toward less aggressive antithrombotic regimens after TAVR, using the minimum necessary to prevent valve thrombosis while keeping bleeding risk manageable. This is an area where treatment is highly individualized, and the “right” regimen depends on your specific combination of clot risk and bleeding risk.

Delirium and Cognitive Effects

Confusion and disorientation in the days following TAVR, formally called postoperative delirium, affects roughly one in five patients. A study comparing TAVR and surgical valve replacement found delirium rates of about 19% and 21%, respectively, though after adjusting for age and other health factors, the odds of delirium were actually lower in the TAVR group. Regardless of which procedure caused it, delirium was associated with a more than threefold higher risk of death within six months.²⁵

A more recent study pinpointed independent predictors of delirium after TAVR: lower baseline cognitive scores, elevated white blood cell counts, and use of non-femoral access routes. Patients who experienced delirium had longer hospital stays, slower functional recovery, and higher one-year mortality. Interestingly, formal cognitive testing over time did not show an accelerated cognitive decline in patients who had delirium, suggesting that those affected may have had preexisting cognitive vulnerability rather than new brain injury from the procedure.²⁶ Preliminary evidence also suggests that maintaining physical activity before and after TAVR may protect against cognitive decline in the following year.²⁷

Sex Differences in Complications

Women and men face different complication profiles after TAVR. In a study of nearly 18,000 transfemoral TAVR patients, women had a 50% higher rate of life-threatening or major bleeding compared to men, while stroke rates and 30-day mortality were similar between the sexes.²⁸ A subanalysis from the POPular TAVI trial confirmed that major or life-threatening bleeding was more common in women, and most of these events originated at the access site.²⁹ The difference is driven largely by women’s smaller artery sizes relative to the catheter, the same factor that predicts vascular complications overall.

Despite higher bleeding and vascular complication rates, some data suggest that women may have equivalent or even slightly better survival than men in the short term after TAVR.³⁰ The reasons aren’t entirely clear, but the pattern highlights that complication types matter as much as complication counts. More vascular events don’t necessarily translate into worse survival if they’re managed effectively.

Readmissions

Coming back to the hospital within 30 days of TAVR is common. In a nationwide analysis of over 12,000 patients, the 30-day readmission rate was about 18%. The strongest predictor was a prolonged initial hospital stay of more than five days, followed by kidney injury during the index hospitalization, multiple chronic conditions, and discharge to a skilled nursing facility rather than home.³¹ Readmissions were driven by a mix of cardiac issues (heart failure, arrhythmias) and non-cardiac problems (infections, kidney trouble, respiratory issues). Patients who had a straightforward transfemoral approach and were discharged home within a few days had substantially lower readmission risk.

Anesthesia Approach

TAVR can be performed under general anesthesia or with conscious sedation, where you’re awake but relaxed and numb at the access site. A randomized trial comparing the two found that outcomes were equivalent for a composite of death, stroke, heart attack, kidney injury, and infection.³² A large observational analysis found that conscious sedation was associated with small reductions in in-hospital and 30-day mortality, shorter hospital stays, and a higher chance of going home directly, though the authors noted that the advantage was smaller than traditional statistical methods had previously suggested.³³ The trend across high-volume centers has shifted strongly toward conscious sedation for straightforward transfemoral cases, partly because avoiding a general anesthetic reduces the need for blood-pressure-supporting medications and can simplify recovery.

Long-Term Valve Durability

As TAVR has expanded to younger patients with longer life expectancies, the question of how long these valves last has become urgent. A systematic review comparing early-generation TAVR valves with surgical valves found that TAVR valves appeared more susceptible to structural deterioration and were associated with higher rates of regurgitation and reintervention over one-to-five-year periods.³⁴ However, newer-generation valves have substantially improved. In the PARTNER-2 trial, the earlier SAPIEN XT valve showed significantly higher five-year rates of structural valve deterioration and valve failure than surgical valves, but the subsequent SAPIEN 3 valve showed no significant difference from surgery on these same durability measures over five years.³⁵

Five years of data is reassuring but not the whole story. A 50-year-old receiving TAVR needs the valve to hold up for decades, and data beyond ten years simply don’t exist yet for current-generation devices. This is one of the reasons many heart teams still favor surgical replacement in younger, lower-risk patients. If a TAVR valve does deteriorate over time, a second TAVR valve can potentially be placed inside the first one, a procedure known as valve-in-valve TAVR, but this comes with its own size constraints and elevated risk of coronary obstruction. The durability question will increasingly shape who gets TAVR and who gets surgery as the procedure continues to move into younger populations.

Annulus Rupture

One of the rarest but most dramatic structural complications is rupture of the aortic annulus, the ring of tissue where the valve sits. The force of balloon expansion during valve deployment can tear through this ring, especially if it is heavily calcified and rigid. Rupture can occur at different levels, above, within, or below the annulus ring, and requires immediate action. Traditionally this has meant emergency open-heart surgery, but case reports describe successful percutaneous repair as a less invasive alternative for patients who are too sick for surgery.³⁶ Pre-procedure CT measurement of the annulus and careful valve sizing are the primary defenses against this complication. Oversizing the valve relative to the annulus increases the risk, and operators walk a fine line between choosing a large enough valve to prevent paravalvular leak and a small enough one to avoid rupture.