Physical examination in valvular aortic stenosis: correlation with stenosis severity and prediction of clinical outcome

The common pathobiology between coronary artery disease and calcific aortic stenosis: Evidence and clinical implications

Calcific aortic valve stenosis (CAS), the most prevalent valvular disease worldwide, has been demonstrated to frequently occur in conjunction with coronary artery disease (CAD), the third leading cause of death worldwide. Atherosclerosis has been proven to be the main mechanism involved in CAS and CAD. Evidence also exists that obesity, diabetes, and metabolic syndrome (among others), along with specific genes involved in lipid metabolism, are important risk factors for CAS and CAD, leading to common pathological processes of atherosclerosis in both diseases. Therefore, it has been suggested that CAS could also be used as a marker of CAD. An understanding of the commonalities between the two conditions may improve therapeutic strategies for treating both CAD and CAS. This review explores the common pathogenesis and disparities between CAS and CAD, alongside their etiology. It also discusses clinical implications and provides evidence-based recommendations for the clinical management of both diseases.

Screening for aortic stenosis using physical examination and echocardiography

Most patients with aortic stenosis (AS) can be treated with either traditional surgical aortic valve replacement or newly emerged transcatheter aortic valve implantation. Therefore, the early and appropriate detection of significant AS has become more important for avoiding overlooking patients who require treatment. AS is initially detected by the presence of a systolic ejection murmur (SEM). However, it is time-consuming and expensive for all subjects presenting with SEM to undergo comprehensive standard echocardiography using high-end ultrasound machines since the SEM is audible in a large proportion of elderly patients and is not specific for significant AS. Therefore, further physical examination and/or focused cardiac ultrasound (FoCUS) is required to determine whether patients with a SEM should be referred for standard echocardiography. One or more abnormal physical findings in addition to a SEM can rule out a certain proportion of normal cases without overlooking severe AS. Most of the previous studies suggesting the usefulness of FoCUS in screening for valvular heart disease only used visual impressions in their assessment of AS. By contrast, visual AS and calcification scores are good objective parameters in screening for AS with FoCUS. Patients with severe AS and patients with a high probability of AS-related events are rarely overlooked even if comprehensive standard echocardiography is performed only when either (or both) of the FoCUS scores is 3 or more. The appropriate combination of physical examinations and FoCUS to screen for AS is discussed in this review article.

Management of Patients With Aortic Valve Stenosis

With increased life expectancy and aging of the population, aortic stenosis is now one of the most common valvular heart diseases. Early recognition and management of aortic stenosis are of paramount importance because untreated symptomatic severe disease is universally fatal. The advent of transcather aortic valve replacement technologies provides exciting avenues of care to patients with this disease in whom traditional surgical procedures could not be performed or were associated with high risk. This review for clinicians offers an overview of aortic stenosis and updated information on the current status of various treatment strategies. An electronic literature search of PubMed, MEDLINE, EMBASE, and Scopus was performed from conception July 1, 2016, through November 30, 2017, using the terms aortic stenosis, aortic valve replacement, transcatheter aortic valve replacement (TAVR), transcatheter aortic valve insertion (TAVI), surgical aortic valve replacement, aortic stenosis flow-gradient patterns, low-flow aortic valve stenosis, natural history, stress testing, pathophysiology, bicuspid aortic valve, and congenital aortic valve disease.

Carotid Doppler sonography: additional tool to assess hemodynamic improvement after transcatheter aortic valve implantation

PURPOSE

The aim of our study was to assess the arterial cerebral blood flow variations in patients with aortic valve stenosis, immediately after the transcatheter aortic valve implantation (TAVI).

METHODS

The study population includes 62 consecutive patients who underwent TAVI for aortic valve stenosis (95%) and sugical bioprosthesis degeneration (5%). Carotid Doppler examination was performed recording blood flow, systolic peak velocity, time average mean velocity and mean acceleration time at baseline, after balloon aortic valvuloplasty, and within 10 min after the device release.

RESULTS

A significant improvement of blood flow was recorded at the end of the procedure (from 315.05 ± 141.72 to 538.67 ± 277.46 ml/min; P < 0.00001). The systolic peak velocity and the time average mean velocity increased from 52.27 ± 14.29 to 78.89 ± 20.48 cm/s (P < 0.00001) and from 12.24 ± 4.74 to 21.21 ± 9 cm/s (P < 0.00001), respectively. Consensually, the mean acceleration time decreased from 0.22 ± 0.02 to 0.03 ± 0.02 s (P < 0.00001) after the procedure.

CONCLUSION

Monitoring of Doppler measurements may be a useful and noninvasive method to assess acutely the improvement of hemodynamic flow after TAVI, specifically for the cerebral district.

Knowledge Gaps in Cardiovascular Care of the Older Adult Population: A Scientific Statement From the American Heart Association, American College of Cardiology, and American Geriatrics Society

The incidence and prevalence of most cardiovascular disorders increase with age, and cardiovascular disease is the leading cause of death and major disability in adults ≥75 years of age; however, despite the large impact of cardiovascular disease on quality of life, morbidity, and mortality in older adults, patients aged ≥75 years have been markedly underrepresented in most major cardiovascular trials, and virtually all trials have excluded older patients with complex comorbidities, significant physical or cognitive disabilities, frailty, or residence in a nursing home or assisted living facility. As a result, current guidelines are unable to provide evidence-based recommendations for diagnosis and treatment of older patients typical of those encountered in routine clinical practice. The objectives of this scientific statement are to summarize current guideline recommendations as they apply to older adults, identify critical gaps in knowledge that preclude informed evidence-based decision making, and recommend future research to close existing knowledge gaps. To achieve these objectives, we conducted a detailed review of current American College of Cardiology/American Heart Association and American Stroke Association guidelines to identify content and recommendations that explicitly targeted older patients. We found that there is a pervasive lack of evidence to guide clinical decision making in older patients with cardiovascular disease, as well as a paucity of data on the impact of diagnostic and therapeutic interventions on key outcomes that are particularly important to older patients, such as quality of life, physical function, and maintenance of independence. Accordingly, there is a critical need for a multitude of large population-based studies and clinical trials that include a broad spectrum of older patients representative of those seen in clinical practice and that incorporate relevant outcomes important to older patients in the study design. The results of these studies will provide the foundation for future evidence-based guidelines applicable to older patients, thereby enhancing patient-centered evidence-based care of older people with cardiovascular disease in the United States and around the world.

The Preoperative Patient With a Systolic Murmur

Context:

Patients with undifferentiated systolic murmurs present commonly during the perioperative period. Traditional bedside assessment and auscultation has not changed significantly in almost 200 years and relies on interpreting indirect acoustic events as a means of evaluating underlying cardiac pathology. This is notoriously inaccurate, even in expert cardiology hands, since many different valvular and cardiac diseases present with a similar auditory signal.

Evidence Acquisition:

The data on systolic murmurs, physical examination, perioperative valvular disease in the setting of non-cardiac surgery is reviewed.

Results:

Significant valvular heart disease increases perioperative risk in major non-cardiac surgery and increases long term patient morbidity and mortality. We propose a more modern approach to physical examination that incorporates the use of focused echocardiography to allow direct visualization of cardiac structure and function. This improves the diagnostic accuracy of clinical assessment, allows rational planning of surgery and anaesthesia technique, risk stratification, postoperative monitoring and appropriate referral to physicians and cardiologists.

Conclusions:

With a thorough preoperative assessment incorporating focused echocardiography, anaesthetists are in the unique position to enhance their role as perioperative physicians and influence short and long term outcomes of their patients.

Clinical pearls in perioperative medicine

At the 2001 annual meeting of the American College of Physicians (ACP), a new and innovative teaching format, the "Clinical Pearls" session, was introduced. Clinical Pearls sessions were designed to teach physicians using clinical cases. The session format involves specialty speakers presenting a number of short cases to a physician audience. Each case is followed by a multiple-choice question, answered by each attendee using an electronic audience-response system. After a summary of the answer distribution is shown, the correct answer is displayed and the speaker discusses important teaching points and clarifies why one answer is most clinically appropriate. Each case presentation ends with 1 or 2 "Clinical Pearls," defined as a practical teaching point, supported by the literature, and generally not well known to most internists. The Clinical Pearls sessions are consistently one the most popular and well attended sessions at the American College of Physicians' national meeting each year. Herein, we present the Clinical Pearls in Perioperative Medicine, presented at the ACP National Meeting in San Francisco, California, April 11-13, 2013.

Acquired aortic stenosis

Aortic stenosis is the most commonly encountered valvular disease in the elderly, with approximately 2-3% of individuals over 65 years of age afflicted. The most common cause of acquired aortic stenosis is calcific degeneration, characterized by a slowly progressive, asymptomatic period which can last decades. Once symptomatic, the clinical manifestation of aortic stenosis is from functional obstruction of left ventricular outflow and the additional hemodynamic effects on the left ventricle and vasculature. With advances in echocardiography, individuals with aortic stenosis are increasingly diagnosed in the asymptomatic latent period. However, echocardiographic measures alone cannot identify clinically significant outflow obstruction as there is considerable overlap in hemodynamic severity between symptomatic and asymptomatic individuals. Current clinical guidelines predicate the timing of surgical valve replacement on the presence or absence of symptoms. Management for symptomatic, significant stenosis is surgical valve replacement as there are no current medical therapies reliably proven to decrease aortic stenosis severity or improve long-term outcomes. However, recent retrospective studies have demonstrated an association between atherosclerotic disease risk factors, such as hyperlipidemia and aortic stenosis. Given these findings, there are now advocates for prospective primary prevention trials for aortic stenosis in patients with mild or moderate valvular disease. The following paper will discuss etiology, diagnostic evaluation and therapeutic options of acquired aortic stenosis. This review will discuss etiology, diagnostic evaluation, and therapeutic options of acquired aortic stenosis.

Doppler-detected valve movement in aortic stenosis: a predictor of adverse outcome

BACKGROUND

The absence of auscultatory aortic valve closure sound is associated with severe aortic stenosis. The absence of Doppler-derived aortic opening (Aop ) or closing (Acl ) may be a sign of advanced severe aortic stenosis.

HYPOTHESIS

Absent Doppler-detected Aop or Acl transient is indicative of very severe aortic stenosis and is associated with adverse outcome.

METHODS

A total of 118 consecutive patients with moderate (n = 63) or severe aortic stenosis (n = 55) were included. Aop and Acl signals were identified in a blinded fashion by continuous-wave Doppler. Patients with and without Aop and Acl were compared using χ(2) test for dichotomous variables and analysis of variance for continuous variables. The associations of Aop and Acl with aortic valve replacement were determined.

RESULTS

Aop or Acl were absent in 22 of 118 patients. The absence of Aop or Acl was associated with echocardiographic parameters of severe aortic stenosis. The absence of Aop or Acl was associated with incident aortic valve replacement (36.4% vs 7.3%, respectively, P < 0.001). Even in patients with aortic valve area <1 cm(2) , the absence of Aop or Acl was still associated with increased rate of aortic valve replacement (42.1% vs 13.9%, respectively, P = 0.019) and provided incremental predictive value over peak velocity.

CONCLUSIONS

In a typical population of patients with aortic stenosis, approximately 1 in 6 has no detectible aortic valve opening or closing Doppler signal. The absence of an Aop or Acl signal is a highly specific sign of severe aortic stenosis and is associated with incident aortic valve replacement.

Core competency review: aortic stenosis and noncardiac surgery

Aortic stenosis (AS) poses a risk of adverse cardiac events for patients undergoing surgical procedures. Perioperative mortality for patients with severe AS is as high as 14%. This review examines the accuracy of the history and physical examination in detecting AS and, subsequently, in assessing severity. The utility of echocardiography is addressed, and the relevant pathophysiology of AS is summarized. We also summarize what is known about perioperative risk for patients with AS.

The role of routine pre-operative bedside echocardiography in detecting aortic stenosis in patients with a hip fracture

The prevalence and severity of aortic stenosis in unselected patients admitted with a hip fracture is unknown. Derriford Hospital operates a routine weekday, pre-operative, targeted bedside echocardiography examination on all patients admitted with a hip fracture. We carried out a prospective service evaluation for 13 months from October 2007 on all 501 admissions, of which 374 (75%) underwent pre-operative echocardiography. Of those patients investigated, 8 (2%) had severe, 24 (6%) moderate and 113 (30%) had mild aortic stenosis or aortic sclerosis. Eighty-seven of 278 (31%) patients with no murmur detected clinically on admission had aortic stenosis on echocardiography and of the 96 patients in whom a murmur was heard pre-operatively, 30 (31%) had a normal echocardiogram. Detection of a murmur does not necessarily reflect the presence of underling aortic valve disease. However, if a murmur is heard then the likelihood of the lesion's being moderate or severe aortic stenosis is increased (OR 8.5; 95% CI 3.8-19.5). Forty-four (12%) of our unselected patients with fractured femur had either moderate or severe aortic stenosis (with or without moderate or severe left ventricular failure), or mild stenosis with moderately or severely impaired left ventricular function.

Carotid artery examination, an important tool in patient evaluation

Examination of the arteries is an age old medical tradition. Examination of the carotid artery is of unique importance because it is an easily accessible large artery. Through the methods of inspection, palpation, and auscultation, carotid artery examination gives clinicians important diagnostic clues about the health and disease of the patient. Inspection and palpation of the carotid give insight into left ventricular systolic function and distinguish types of valvular heart disease. Auscultation identifies patients with high-risk atherosclerosis. In most cases carotid examination is neither sensitive nor specific, but in the correct clinical context it offers important evidence leading to specific diagnoses and treatment. In this review, we discuss the examination of the carotid artery under normal conditions and describe how abnormalities in the carotid artery examination are indicators of disease.

Echo-tracking assessment of carotid artery stiffness in patients with aortic valve stenosis

BACKGROUND

There is little information about mechanical properties of large arteries in patients (pts) with aortic stenosis (AS).

METHODS

Nineteen patients with AS (aortic valve area: 0.88 +/- 0.29 cm(2)) and 24 control subjects without AS but with a similar distribution of risk factors were recruited. beta index, pressure-strain elastic modulus (Ep), arterial compliance (AC), augmentation index (AIx), and local pulse-wave velocity (PWV) were obtained at the level of right common carotid artery (CCA) by a real time echo-tracking system. Time to dominant peak of carotid diameter change waveform, corrected for heart rate (tDPc), and maximum rate of rise of carotid diameter (dD/dt) were measured. Systemic arterial compliance (SAC) was also calculated. Parameters of AS severity (mean gradient, valve area, stroke work loss [SWL]) were determined.

RESULTS

tDPc was higher in patients with AS than in controls (7.9 +/- 0.6 vs. 6.6 +/- 0.7, P < 0.0001) while dD/dt was lower (5.3 +/- 3.6 mm/s vs. 7.8 +/- 2.8 mm/s, P = 0.01). AIx was significantly higher in AS group (32.5 +/- 13.6% vs. 20.6 +/- 12.2%, P = 0.005) and had a linear correlation both with tDPc (r = 0.63, P < 0.0001) and with dD/dt (r =-0.38, P = 0.01). There was a significant correlation between carotid AC and SAC (r = 0.49, P = 0.03), but only carotid AC was related to SWL (r = 0.51, P = 0.02), while SAC was not (P = 0.26).

CONCLUSIONS

AIx was the only parameter of arterial rigidity found to be higher in patients with AS than in controls. Carotid AC showed a significant correlation with SAC and it seemed to be more closely related to AS severity than to SAC.

Aortic valve stenosis

Calcific aortic stenosis (AS) is primarily a disease of the elderly, possessing features that are biomechanical as well as systemic and inflammatory in nature, with risk factors and histopathology similar to atherosclerosis. To date no medical therapy has been shown to conclusively alter the progression of the disease, and for those with symptomatic AS, aortic valve replacement (AVR) is advocated. Factors that may alert the physician to an accelerated progression of calcific aortic valvular disease toward severe symptomatic AS include moderate aortic valve calcification, chronically dialyzed patients, and patients 80 years and older. There remains significant morbidity and mortality associated with AVR, and new techniques and technologies for AVR are being developed. For those who undergo successful AVR the long-term prognosis is good. A substantial number of patients with symptomatic AS present for anesthesia care for a variety of procedures. A thorough, modern understanding of AS and its course are necessary for the anesthesiologist to guide the patient through the perioperative period.

Samuel A. Levine and the history of grading systolic murmurs

Murmurs were described first by Laennec in 1819, after which the significance of a murmur became a matter of debate. By the late 19th century, many physicians regarded systolic murmurs as "organic," whereas others believed that they were often "functional." Samuel Levine became a central figure in separating functional from organic systolic murmurs. Freeman and Levine's 1933 study of 1,000 "noncardiac" subjects determined the frequency, cause, and significance of systolic murmurs. Murmurs were rated on a scale of 1 to 6 grades of intensity. Approximately 20% of their patients had grade 1 or 2 systolic murmurs. Hypertension, fever, tachycardia, and anemia were common factors, and the murmurs were considered functional because they would often disappear when these causes were controlled. Of 19 subjects with grade 3 or 4 murmurs, all were determined to have organic heart disease or anemia. Thus, louder systolic murmurs were found to be a significant finding, as were the cause, location, and effects of posture. They concluded that systolic murmurs often have an explanation and that their grade can be useful in the diagnosis and prognosis. They cautioned that a loud systolic murmur did not necessarily indicate a bad prognosis or even serious heart disease. Levine's system of grading a systolic murmur is valuable and persists into the 21st century.

Valvular heart disease: focus on women

Calcific aortic stenosis is a disease of the elderly and aortic valve replacement should always be considered for severe symptomatic disease; comorbidities, not age, determine surgical risk. Aortic regurgitation imposes a pressure and volume load on the left ventricle so that close monitoring is needed to identify patients at risk for irreversible left ventricular dysfunction, although symptoms are the most common indication for valve replacement. Early intervention now is recommended for rheumatic mitral stenosis due to the effectiveness of percutaneous balloon valvotomy. Earlier intervention also may be considered in selected patients with mitral regurgitation at experienced centers when valve anatomy is favorable for a successful repair. Semiquantitative descriptors of regurgitation as mild, moderate, or severe are no longer adequate; management of adults with chronic valve disease requires quantitation of both the severity of valve disease and of left ventricular size and systolic function.

Indications for aortic valve replacement in aortic stenosis

Aortic stenosis is a common condition, particularly in the elderly. The treatment is surgical, and any patient with symptomatic severe aortic stenosis should be considered for aortic valve replacement. Aortic stenosis causes an increase in afterload to the left ventricle, which when severe can lead to hemodynamic instability. Although the therapy of aortic stenosis is valve replacement, determining whether a patient has symptoms and accurately assessing the severity of stenosis can be difficult. The management of patients with severe aortic stenosis in the intensive care unit setting can be very challenging, particularly when comorbid medical conditions make aortic valve replacement difficult. This article reviews the diagnosis of aortic stenosis, methods of assessing symptoms and severity, and management of severe symptomatic stenosis, particularly in the intensive care unit setting. Components of the history that suggest symptomatic aortic stenosis are presented. The role of physical examination is discussed, as are the echocardiographic means of determining stenosis severity. Other means of assessing severity are addressed, as are circumstances in which there can be difficulty in interpretation, such as severe aortic stenosis and left ventricular dysfunction. Management of patients, focusing on the intensive care unit setting, is reviewed, with a focus on the timing of aortic valve replacement.

Assessment of severity of aortic stenosis through time-frequency analysis of murmur

STUDY OBJECTIVE

The accurate and inexpensive noninvasive assessment of the presence and severity of aortic stenosis remains a challenge. In this study, we performed spectral analysis on the murmurs of a group of patients with this disease in order to assess its severity.

DESIGN

An electronic stethoscope was used to generate a spectral analysis of murmurs in patients with aortic stenosis. The durations of the spectra at different frequencies (ie, 200, 250, and 300 Hz) were correlated to the Doppler echocardiogram-derived mean and peak pressure gradients. Heart murmurs from the patients were recorded, and the spectra of the recordings were produced via fast-Fourier transformation. The duration of the spectra above the three given frequencies was then measured.

PATIENTS

Forty-one patients (age range, 45 to 94 years; mean age, 68 years) met the inclusion criteria, which included a minimum ejection fraction of 40% and no other significant systolic murmur or coexistent valve disease.

RESULTS

The peak pressure gradient measured via Doppler echocardiogram ranged from 15.3 to 185 mm Hg with the mean of 63 mm Hg. The duration of the spectra of > 300 Hz correlated best with the peak pressure gradient measured using the Doppler echocardiogram. An exponential regression model was created showing a significant correlation coefficient of r = 0.86 (p < 0.0001).

CONCLUSIONS

This study demonstrated a good correlation between the duration of spectra at 300 Hz and the Doppler derived peak pressure gradient. This simple and inexpensive technique may prove to be valuable in the evaluation and monitoring of patients with suspected and proven aortic stenosis.

The patient with a systolic murmur: severe aortic stenosis may be missed during cardiovascular examination

Significant aortic stenosis is prevalent amongst elderly people. It may be subclinical, manifesting only as a murmur, but can still cause unexpected death with little warning after symptoms develop. Recent studies have highlighted the unreliability of the classical clinical signs of severe aortic stenosis, leading to concern that some patients may not be referred appropriately for echocardiography. Here, we review the evidence for the accuracy of each sign. We suggest that the assessment of the patient with a systolic murmur should be reappraised, and offer guidelines toward improving the recognition of aortic stenosis in the community.