Due to the aging population, aortic stenosis remains the most common valvular heart disease. Aortic stenosis in elderly and senile patients is a problem of both a diagnostic nature and a choice of treatment. Despite new advances in the field of cardiac surgery, primarily the development of methods for transcatheter aortic valve replacement (or implantation) (TAVR), problems associated with concomitant diseases and care for the elderly remain relevant.
Increased life expectancy due to advances in modern medicine entails an increase in the number of diagnosed aortic stenoses. The prevalence of aortic stenosis in patients under 60 years of age is low, but it increases in patients over 80 years of age by approximately 10%. The severity of aortic stenosis also increases with age, and 1 in 8 people over 75 years of age have moderate or severe aortic stenosis.
All of this represents a significant public health problem that is likely to get worse as the population ages.
Epidemiology of aortic valve changes
Changes in the aortic valve are the most common among age-associated (degenerative) changes in the valvular apparatus of the heart in elderly and senile people and are observed in more than 25% of patients over the age of 65. Most patients experience moderate thickening of the leaflets and normal function of the valve itself – the so-called aortic sclerosis. However, 2–5% of these patients are diagnosed with significant aortic stenosis with impaired blood outflow from the left ventricle.
Risk factors and pathogenesis of aortic stenosis development
Clinical risk factors for the development of degenerative aortic valve stenosis are similar to those for coronary atherosclerosis. Traditional risk factors for diseases of the cardiovascular system, such as age, male gender, smoking, elevated levels of low-density lipoproteins and cholesterol in the blood, arterial hypertension, and metabolic syndrome, are associated with the occurrence and progression of aortic stenosis. Elderly patients with aortic stenosis usually have underlying coronary or peripheral vascular disease. The risk factors associated with the onset of the disease may differ from those that contribute to the development of the disease, but the disease progresses more rapidly in older age.
Age-associated changes in the aortic valve are a chronic, progressive condition. Moderate fibrous-calcific changes in the aortic valve leaflets, as they progress, reach almost the degree of ossification and cause significant obstruction of blood flow from the left ventricle. Primary changes in the aortic valve include disorganized collagen fibers, chronic inflammatory cells, extracellular bone matrix proteins, and bone minerals, which gives grounds to discuss the chronic inflammatory nature of the process. Hemodynamic stress initiates endothelial dysfunction, which also contributes to the destruction of the aortic valve. Progressive calcification of the valve leaflets leads to an increase in their stiffness and a narrowing of the opening. Over time, the increased pressure gradient in the aorta leads to pressure overload in the left ventricle. The wall of the left ventricle thickens, and the ventricle hypertrophies. Sustained hypertrophy and pressure over time form left ventricular diastolic dysfunction and deformation, leading to left ventricular failure.
Aortic stenosis and comorbidity in the elderly and senile age
When evaluating older patients for aortic stenosis, clinicians often focus only on the valve as the main cause of the patient’s complaints. However, the presence of concomitant, often severe, diseases should be taken into account. Concomitant diseases can affect the outcome of surgical treatment, which makes a comprehensive examination of the patient necessary. In older patients with severe pulmonary diseases, such as pulmonary hypertension or chronic obstructive pulmonary disease, it may be difficult to recognize whether symptoms are signs of cardiovascular or pulmonary disease. Aortic valve replacement may not improve clinical symptoms or outcomes. In patients who underwent AVR, significant impairment of pulmonary function was observed in 60% of cases, and more than 30% of patients required oxygen therapy. Increased morbidity and mortality have been observed in patients with serious pulmonary pathology who undergo aortic valve replacement. Another small cohort study found that 77% of cases had significant sleep-disordered breathing. Chronic kidney disease, liver disease, and anemia were independently associated with increased mortality after aortic valve replacement.
Difficulties in diagnosing aortic stenosis in elderly and senile age
When examining elderly and senile patients with aortic stenosis, it is important to carefully and comprehensively collect a detailed history. The three main symptoms of aortic stenosis that indicate the need for urgent valve replacement are angina, syncope, or symptoms of heart failure (including orthopnea, edema, paroxysmal nocturnal dyspnea). These symptoms may be difficult to identify in older adults because most patients have limited mobility or may not have active complaints. An integral part of the diagnosis is the involvement of relatives or caregivers who may notice changes in the activity, appetite, and general condition of the elderly person. Exercise testing (under close supervision) can identify asymptomatic patients; By assessing gait, it is possible to determine whether aortic stenosis is the cause of hemodynamic disturbances. Although patients may have asymptomatic aortic stenosis due to the absence of functional impairment, a very high incidence of echocardiographically proven significant aortic stenosis is still possible, and patients should be guaranteed specialist follow-up.
It is important to determine whether a symptom is related to aortic stenosis since the presence of symptoms influences patient management. Patients who are limited in mobility, deconditioned, or have oxygen-dependent lung disease may experience shortness of breath unrelated to valve disease and will not benefit from valve replacement.
A physical examination can indicate the severity of aortic stenosis and help assess the burden on the cardiovascular system. Due to aortic valve stenosis and left ventricular hypertrophy, the force of heart contractions increases and a bifurcated sharp systolic murmur occurs. Attenuated systolic flutter is best heard in the second intercostal space to the right or left of the sternum, but vessel wall stiffness may mask a bifurcated systolic murmur, and dorsal kyphosis may make the flutter difficult to detect. In older patients, the intensity of the tremor may even decrease as stroke volume decreases. In severe aortic stenosis, the aortic component of the second heart sound is either smoothed or absent. If aortic stenosis is suspected based on physical examination, echocardiography is necessary.
Treatment of Aortic Stenosis in Elderly and Senile Patients
Aortic stenosis is a prevalent cardiovascular disorder among the elderly population, characterized by the narrowing of the aortic valve opening, which restricts blood flow from the heart to the rest of the body. As the global population ages, the management of aortic stenosis in elderly and senile patients has become increasingly important. This condition can lead to significant health complications, including heart failure, reduced physical functioning, and increased mortality. The approach to aortic stenosis treatment in elderly in this demographic must consider the unique physiological and medical challenges posed by older age.
Conclusion
After valve replacement, careful monitoring and control of concomitant diseases is essential. Elderly and senile patients are at higher risk for bleeding, renal failure, arrhythmias, blockade of the cardiac conduction system, and cognitive impairment. Patients with severe aortic stenosis with severe symptoms have a significant decrease in preoperative functional status and severe malnutrition, which leaves patients in the high-risk category in the postoperative period.
Hospitalization is invariably associated with decreased functional status, and postoperative delirium can lead to cognitive decline. Activation and rehabilitation after valve transplantation are important to improve outcomes in elderly and senile patients after AVR. Close monitoring by the treating physician and geriatrician is warranted to evaluate long-term postoperative complications or changes in health status.
