Echocardiography in the evaluation of systolic murmurs of unknown cause

Ventricular Septal Rupture in Cardiac Sarcoidosis Diagnosed by Point-of-Care Ultrasound

A 60-year-old female with cardiac sarcoidosis and a history of ventricular aneurysm presented with acute palpitations and diaphoresis. Bedside point-of-care ultrasound (POCUS) identified a ventricular septal rupture (VSR) with left-to-right shunting, suggesting acute rupture of the aneurysm. This case highlights the critical role of POCUS in a rare and life-threatening complication of cardiac sarcoidosis, expediting management and improving patient outcomes.

Impact of Transaortic Valve Flow Velocity on the Development of Systolic Heart Murmurs

Background

Although cardiac auscultation plays an essential role in detecting valvular heart diseases, false-positive rates due to innocent heart murmurs remain a concern because accelerated transaortic valve blood flow can be a major contributor to systolic heart murmurs. In this study we investigated the effect of transaortic valve flow velocity on the development of systolic heart murmurs.

Methods and Results

Cardiac auscultation was performed in 571 patients referred for echocardiography and systolic heart murmur was detected in 103 (18.0%). Maximum transaortic valve flow velocity was higher in patients with murmurs than in those without (2.02 vs. 1.34 m/s, P<0.001; area under the receiver operating characteristic curve, 0.82). A cutoff maximum transaortic flow velocity of 1.7 m/s predicted systolic heart murmurs (sensitivity, 65%; specificity, 88%). The incidence of heart murmur was associated with higher maximum transaortic valve flow velocity (<1.7 m/s, 7.3%; 1.7-2.5 m/s, 50.0%; >2.5 m/s, 73.5%). Multivariate analysis revealed the maximum transaortic valve flow velocity as an independent predictor of systolic heart murmurs (hazard ratio, 9.18; 95% confidence interval, 5.35-15.75; P<0.001).

Conclusions

Accelerated transaortic valve flow velocity is an important determinant of systolic heart murmurs. Systolic heart murmurs can be heard before the transaortic valve flow velocity reaches the clinically significant aortic stenosis criterion, which can constitute a considerable number of innocent heart murmurs.

Rapid detection and interpretation of heart murmurs using phonocardiograms, transfer learning and explainable artificial intelligence

Cardiovascular disease, which remains one of the main causes of death, can be prevented by early diagnosis of heart sounds. Certain noisy signals, known as murmurs, may be present in heart sounds. On auscultation, the degree of murmur is closely related to the patient's clinical condition. Computer-aided decision-making systems can help doctors to detect murmurs and make faster decisions. The Mel spectrograms were generated from raw phonocardiograms and then presented to the OpenL3 network for transfer learning. In this way, the signals were classified to predict the presence or absence of murmurs and their level of severity. Pitch level (healthy, low, medium, high) and Levine scale (healthy, soft, loud) were used. The results obtained without prior segmentation are very impressive. The model used was then interpreted using an Explainable Artificial Intelligence (XAI) method, Occlusion Sensitivity. This approach shows that XAI methods are necessary to know the features used internally by the artificial neural network then to explain the automatic decision taken by the model. The averaged image of the occlusion sensitivity maps can give us either an overview or a precise detail per pixel of the features used. In the field of healthcare, particularly cardiology, for rapid diagnostic and preventive purposes, this work could provide more detail on the important features of the phonocardiogram.

Handheld echocardiography for the screening and diagnosis of rheumatic heart disease: a systematic review to inform WHO guidelines

BACKGROUND

Early detection and diagnosis of acute rheumatic fever and rheumatic heart disease are key to preventing progression, and echocardiography has an important diagnostic role. Standard echocardiography might not be feasible in high-prevalence regions due to its high cost, complexity, and time requirement. Handheld echocardiography might be an easy-to-use, low-cost alternative, but its performance in screening for and diagnosing acute rheumatic fever and rheumatic heart disease needs further investigation.

METHODS

In this systematic review and meta-analysis, we searched Embase, MEDLINE, LILACS, and Conference Proceedings Citation Index-Science up to Feb 9, 2024, for studies on the screening and diagnosis of acute rheumatic fever and rheumatic heart disease using handheld echocardiography (index test) or standard echocardiography or auscultation (reference tests) in high-prevalence areas. We included all studies with useable data in which the diagnostic performance of the index test was assessed against a reference test. Data on test accuracy in diagnosing rheumatic heart disease, acute rheumatic fever, or carditis with acute rheumatic fever (primary outcomes) were extracted from published articles or calculated, with authors contacted as necessary. Quality of evidence was appraised using GRADE and QUADAS-2 criteria. We summarised diagnostic accuracy statistics (including sensitivity and specificity) and estimated 95% CIs using a bivariate random-effects model (or univariate random-effects models for analyses including three or fewer studies). Area under the curve (AUC) was calculated from summary receiver operating characteristic curves. Heterogeneity was assessed by visual inspection of plots. This study was registered with PROSPERO (CRD42022344081).

FINDINGS

Out of 4868 records we identified 11 studies, and two additional reports, comprising 15 578 unique participants. Pooled data showed that handheld echocardiography had high sensitivity (0·87 [95% CI 0·76-0·93]), specificity (0·98 [0·71-1·00]), and overall high accuracy (AUC 0·94 [0·84-1·00]) for diagnosing rheumatic heart disease when compared with standard echocardiography (two studies; moderate certainty of evidence), with better performance for diagnosing definite compared with borderline rheumatic heart disease. High sensitivity (0·79 [0·73-0·84]), specificity (0·85 [0·80-0·89]), and overall accuracy (AUC 0·90 [0·85-0·94]) for screening rheumatic heart disease was observed when pooling data of handheld echocardiography versus standard echocardiography (seven studies; high certainty of evidence). Most studies had a low risk of bias overall. Some heterogeneity was observed for sensitivity and specificity across studies, possibly driven by differences in the prevalence and severity of rheumatic heart disease, and level of training or expertise of non-expert operators.

INTERPRETATION

Handheld echocardiography has a high accuracy and diagnostic performance when compared with standard echocardiography for diagnosing and screening of rheumatic heart disease in high-prevalence areas.

FUNDING

World Health Organization.

TRANSLATIONS

For the Chinese, French, Italian, Persian, Portuguese, Spanish and Urdu translations of the abstract see Supplementary Materials section.

Diagnostic accuracy of heart auscultation for detecting valve disease: a systematic review

OBJECTIVE

The objective of this study was to determine the diagnostic accuracy in detecting valvular heart disease (VHD) by heart auscultation, performed by medical doctors.

DESIGN/METHODS

A systematic literature search for diagnostic studies comparing heart auscultation to echocardiography or angiography, to evaluate VHD in adults, was performed in MEDLINE (1947-November 2021) and EMBASE (1947-November 2021). Two reviewers screened all references by title and abstract, to select studies to be included. Disagreements were resolved by consensus meetings. Reference lists of included studies were also screened. The results are presented as a narrative synthesis, and risk of bias was assessed using Quality Assessment of Diagnostic Accuracy Studies-2.

MAIN OUTCOME MEASURES

Sensitivity, specificity and likelihood ratios (LRs).

RESULTS

We found 23 articles meeting the inclusion criteria. Auscultation was compared with full echocardiography in 15 of the articles; pulsed Doppler was used as reference standard in 2 articles, while aortography and ventriculography was used in 5 articles. One article used point-of-care ultrasound. The articles were published from year 1967 to 2021. Sensitivity of auscultation ranged from 30% to 100%, and specificity ranged from 28% to 100%. LRs ranged from 1.35 to 26. Most of the included studies used cardiologists or internal medicine residents or specialists as auscultators, whereas two used general practitioners and two studied several different auscultators.

CONCLUSION

Sensitivity, specificity and LRs of auscultation varied considerably across the different studies. There is a sparsity of data from general practice, where auscultation of the heart is usually one of the main methods for detecting VHD. Based on this review, the diagnostic utility of auscultation is unclear and medical doctors should not rely too much on auscultation alone. More research is needed on how auscultation, together with other clinical findings and history, can be used to distinguish patients with VHD.

PROSPERO REGISTRATION NUMBER

CRD42018091675.

Mitral Valve Regurgitation Murmurs—Insights from Hemoacoustic Computational Modeling

Mitral regurgitation (MR) is the leakage of blood from the left ventricle into the left atrium during systole through a mitral valve that does not close fully. A systolic murmur is produced by MR and can be used to diagnose this disease. In the current study, we use hemoacoustic simulations to characterize the features of murmurs for a range of severities relevant to chronic MR. The incompressible Navier–Stokes equations are solved using an immersed boundary method to simulate the blood flow. The resultant pressure fluctuations on the lumen wall serve as the source for the murmur, and the murmur propagation through the thorax is modeled as a 3D elastic wave in a linear viscoelastic material. The resulting acceleration on the surface of the thorax is used as a surrogate for the measurement from a stethoscope, and these characteristics of the acceleration signal are examined in detail. We found that the intensity of the MR murmur is lower at the mitral point on the precordium, as compared with the aortic and pulmonic areas. This is somewhat counterintuitive but is supported by other studies in the past. We also found that the intensity of the murmur, as well as the break frequency, are well correlated with the severity of MR, and this information can be useful for automated auscultation and phonocardiographic applications.

Orthopaedic cardiac considerations in emergency

Orthopaedic patients undergoing emergency orthopaedic surgery should be referred for cardiac evaluation only when they are symptomatic or when a specific cardiac intervention is expected to reduce the surgical risk. A preoperative delay of 24-48 h of emergency orthopaedic operations has been associated with increased mortality and poor functional status of the patients. Research in the preoperative setting is almost exclusively retrospective because randomized studies are difficult to be performed and pose serious ethical concerns. Moreover, inevitably, guidelines have a low level of evidence and do not always provide a straightforward framework for the preoperative care of the patients. This editorial revisits the most common clinical cardiology dilemmas for emergency orthopaedic surgery to explore controversies of current recommendations and elaborate on the role of echocardiography in the perioperative period in emergency orthopaedic surgery.

Deep Learning Algorithm for Automated Cardiac Murmur Detection via a Digital Stethoscope Platform

Background Clinicians vary markedly in their ability to detect murmurs during cardiac auscultation and identify the underlying pathological features. Deep learning approaches have shown promise in medicine by transforming collected data into clinically significant information. The objective of this research is to assess the performance of a deep learning algorithm to detect murmurs and clinically significant valvular heart disease using recordings from a commercial digital stethoscope platform. Methods and Results Using >34 hours of previously acquired and annotated heart sound recordings, we trained a deep neural network to detect murmurs. To test the algorithm, we enrolled 962 patients in a clinical study and collected recordings at the 4 primary auscultation locations. Ground truth was established using patient echocardiograms and annotations by 3 expert cardiologists. Algorithm performance for detecting murmurs has sensitivity and specificity of 76.3% and 91.4%, respectively. By omitting softer murmurs, those with grade 1 intensity, sensitivity increased to 90.0%. Application of the algorithm at the appropriate anatomic auscultation location detected moderate-to-severe or greater aortic stenosis, with sensitivity of 93.2% and specificity of 86.0%, and moderate-to-severe or greater mitral regurgitation, with sensitivity of 66.2% and specificity of 94.6%. Conclusions The deep learning algorithm's ability to detect murmurs and clinically significant aortic stenosis and mitral regurgitation is comparable to expert cardiologists based on the annotated subset of our database. The findings suggest that such algorithms would have utility as front-line clinical support tools to aid clinicians in screening for cardiac murmurs caused by valvular heart disease. Registration URL: https://clinicaltrials.gov; Unique Identifier: NCT03458806.

The first 200 years of cardiac auscultation and future perspectives

Cardiac auscultation - even with its limitations - is still a valid and economical technique for the diagnosis of cardiovascular diseases, and despite the growing demand for sophisticated imaging techniques, clinical use of the stethoscope in medical practice has not yet been abandoned. In 1816, René-Théophile-Hyacinthe Laënnec invented the stethoscope, while examining a young woman with suspected heart disease, giving rise to mediated auscultation. He described in detail several heart and lung sounds, correlating them with postmortem pathology. Even today, a correct interpretation of heart sounds, integrated with the clinical history and physical examination, allows to detect properly most of the structural heart abnormalities or to evaluate them in a differential diagnosis. However, the lack of organic teaching of auscultation and its inadequate practice have a negative impact on the clinical competence of physicians in training, also reflecting a diminished academic interest in physical semiotic. Medical simulation could be an effective instructional tool in teaching and deepening auscultation. Handheld ultrasound devices could be used for screening or for integrating and improving auscultatory abilities of physicians; the electronic stethoscope, with its new digital capabilities, will help to achieve a correct diagnosis. The availability of innovative representations of the sounds with phono- and spectrograms provides an important aid in diagnosis, in teaching practice and pedagogy. Technological innovations, despite their undoubted value, must complement and not supplant a complete physical examination; clinical auscultation remains an important and cost-effective screening method for the physicians in cardiorespiratory diagnosis. Cardiac auscultation has a future, and the stethoscope has not yet become a medical heirloom.

Prevalence and diagnostic characteristics of non-clinical mitral regurgitation murmurs in North American Whippets

OBJECTIVES

To assess the prevalence of functional ejection murmurs and murmurs of mitral regurgitation (MR) due to myxomatous mitral valve disease in healthy whippets; to assess the diagnostic value of auscultation to detect MR; and investigate the relationship between age and presence of echocardiographically documented MR (MR_echo).

ANIMALS

A total of 200 healthy client-owned Whippets, recruited at national shows between 2005 and 2009 were involved in this study.

METHODS

Cross-sectional study. Dogs were examined by auscultation by one examiner and Doppler echocardiography by another, and results were compared. Prevalence of types of murmurs and MR_echo were calculated and correlated to age. Accuracy of auscultation to predict MR_echo was calculated.

RESULTS

Left-sided systolic heart murmurs were detected in 185/200 (93%) of dogs. Left apical systolic murmurs (L_apex) were detected in 57/200 (29%) and left basilar systolic murmurs (L_base) in 128/200 of the dogs (64%). MR_echo was present in 76/200 (38%) dogs. Prevalence MR_echo was correlated with age (r = 0.96, p=0.0028). Mitral regurgitation detected by echocardiography was present in 12/78 (15%) of the dogs ≤ 2 years of age and in 59% of the dogs at 7-8 years old. Detection of L_apex predicted MR_echo with sensitivity 65%, specificity 94%, positive predictive value 86%, and negative predictive value 81%; and accuracy improved when only dogs with more intense L_apex (grade ≥ 3/6) were considered.

CONCLUSIONS

Systolic murmurs are common in North American Whippets and this breed exhibits a high prevalence of MR_echo, which may be documented at a relatively early age. Whippets with non-clinical MR_echo may not be identifiable by auscultation alone; echocardiographic examination may be required to exclude a diagnosis of MR. Louder heart murmurs allow more accurate localization in this population.

The feasibility and efficacy of implementing a focused cardiac ultrasound course into a medical school curriculum

BACKGROUND

Teaching cardiac ultrasound to medical students in a brief course is a challenge. We aimed to evaluate the feasibility of teaching large groups of medical students the acquisition and interpretation of cardiac ultrasound images using a pocket ultrasound device (PUD) in a short, specially designed course.

METHODS

Thirty-one medical students in their first clinical year participated in the study. All were novices in the use of cardiac ultrasound. The training consisted of 4 hours of frontal lectures and 4 hours of hands-on training. Students were encouraged to use PUD for individual practice. Finally, the students' proficiency in the acquisition of ultrasound images and their ability to recognize normal and pathological states were evaluated.

RESULTS

Sixteen of 27 (59%) students were able to demonstrate all main ultrasound views (parasternal, apical, and subcostal views) in a six-minute test. The most obtainable view was the parasternal long-axis view (89%) and the least obtainable was the subcostal view (58%). Ninety-seven percent of students correctly differentiated normal from severely reduced left ventricular function, 100% correctly differentiated a normal right ventricle from a severely hypokinetic one, 100% correctly differentiated a normal mitral valve from a rheumatic one, and 88% correctly differentiated a normal aortic valve from a calcified one, while 95% of them correctly identified the presence of pericardial effusion.

CONCLUSIONS

Training of medical students in cardiac ultrasound during the first clinical year using a short, focused course is feasible and enables students with modest ability to acquire the main transthoracic ultrasound views and gain proficiency in the diagnosis of a limited number of cardiac pathologies.

Point-of-care cardiac ultrasound techniques in the physical examination: better at the bedside

The development of hand-carried, battery-powered ultrasound devices has created a new practice in ultrasound diagnostic imaging, called 'point-of-care' ultrasound (POCUS). Capitalising on device portability, POCUS is marked by brief and limited ultrasound imaging performed by the physician at the bedside to increase diagnostic accuracy and expediency. The natural evolution of POCUS techniques in general medicine, particularly with pocket-sized devices, may be in the development of a basic ultrasound examination similar to the use of the binaural stethoscope. This paper will specifically review how POCUS improves the limited sensitivity of the current practice of traditional cardiac physical examination by both cardiologists and non-cardiologists. Signs of left ventricular systolic dysfunction, left atrial enlargement, lung congestion and elevated central venous pressures are often missed by physical techniques but can be easily detected by POCUS and have prognostic and treatment implications. Creating a general set of repetitive imaging skills for these entities for application on all patients during routine examination will standardise and reduce heterogeneity in cardiac bedside ultrasound applications, simplify teaching curricula, enhance learning and recollection, and unify competency thresholds and practice. The addition of POCUS to standard physical examination techniques in cardiovascular medicine will result in an ultrasound-augmented cardiac physical examination that reaffirms the value of bedside diagnosis.

In defence of auscultation: a glorious future?

Auscultation of the heart using a simple stethoscope continues to be a central aspect of the cardiovascular examination despite declining proficiency and availability of competing technologies such as hand-held ultrasound. In the ears and mind of a trained cardiologist, heart sounds can provide important information to help screen for certain diseases such as valvar lesions and many congenital defects. Using emerging technology, auscultation is poised to undergo a transformation that will simultaneously improve the teaching and evaluation of this important clinical skill and create a new generation of smart stethoscopes, capable of assisting the clinician in quickly and confidently screening for heart disease. These developments have important implications for global health, screening of athletes and recognition of congenital heart disease.

The not so innocent heart murmur: a 5-year experience

BACKGROUND

Auckland City Hospital (ACH) established a Heart Murmur Clinic (HMC) with the aim of providing prompt assessment of patients with asymptomatic systolic murmurs. This may lead to early intervention and improved outcomes if significant structural heart disease is detected and reassurance if no significant findings are found. Similar clinics for children have proven beneficial; the benefit of a HMC in an adult population has been difficult to determine.

AIM

To review the clinical demographics and echocardiographic information of patients presenting to our HMC, to assess what proportion of significance structural heart disease had and determine the common structural abnormalities in this population.

METHODS

This is a retrospective review of patients aged ≥15 years presenting to our HMC between March 2010 and December 2015 with an asymptomatic systolic murmur. Patients with previous cardiac surgery or known congenital or valvular heart disease were excluded.

RESULTS

A total of 1221 patients was reviewed over the 5-year period; 980 underwent echocardiography. Significant cardiac disease was detected in 156 patients, with 23 patients requiring surgical intervention over the 5-year period. Significant aortic stenosis (n = 43) and mitral regurgitation (n = 48) were the most common pathologies. Patients > 65 years were more likely to have structural heart disease (16% vs 11%, P < 0.05).

CONCLUSION

Establishing a HMC has allowed the screening of a large number of patients who would otherwise have low priority for assessment. We have identified a large proportion with significant structural disease, which has allowed for early surgical intervention when appropriate and may potentially result in improved patient outcomes.

Utility of Echocardiogram in the Evaluation of Heart Murmurs

Valvular heart disease is a common condition in today's patient population. Accurate characterization of vital cardiac structures has become crucial to early diagnosis and varied treatment options. The advent of ultrasound technology has had a large impact in cardiovascular medicine, particularly in the assessment of valvular heart disease. Today its versatility and availability have allowed it to become one of the most frequently ordered imaging tests for cardiovascular indications. Despite the tremendous evidence that suggests that clinical examinations are still standard of care, a large volume of referrals for echocardiograms suggests differently.

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.

The need for annual echocardiography to detect cabergoline-associated valvulopathy in patients with prolactinoma: a systematic review and additional clinical data

Present recommendations by the US Food and Drug Administration advise that patients with prolactinoma treated with cabergoline should have an annual echocardiogram to screen for valvular heart disease. Here, we present new clinical data and a systematic review of the scientific literature showing that the prevalence of cabergoline-associated valvulopathy is very low. We prospectively assessed 40 patients with prolactinoma taking cabergoline. Cardiovascular examination before echocardiography detected an audible systolic murmur in 10% of cases (all were functional murmurs), and no clinically significant valvular lesion was shown on echocardiogram in the 90% of patients without a murmur. Our systematic review identified 21 studies that assessed the presence of valvular abnormalities in patients with prolactinoma treated with cabergoline. Including our new clinical data, only two (0·11%) of 1811 patients were confirmed to have cabergoline-associated valvulopathy (three [0·17%] if possible cases were included). The probability of clinically significant valvular heart disease is low in the absence of a murmur. On the basis of these findings, we challenge the present recommendations to do routine echocardiography in all patients taking cabergoline for prolactinoma every 12 months. We propose that such patients should be screened by a clinical cardiovascular examination and that echocardiogram should be reserved for those patients with an audible murmur, those treated for more than 5 years at a dose of more than 3 mg per week, or those who maintain cabergoline treatment after the age of 50 years.

[Diagnosis of a systolic murmur among young asymptomatic patient: An assessment of professional practices for the expertise in military medicine]

The finding of a systolic heart murmur is common in medical military practice. Albeit often benign among young healthy adults, it can reveal a valvular or a cardiac disease, which could worsen during workout or expose to risk of a sudden death. This study aims to evaluate the diagnostic efficiency of the military general practitioner when discovering a systolic murmur among young asymptomatic patients.

MATERIALS AND METHODS

During one year, this study involved all the general practitioners of the medical military centres of Brittany and the cardiologists of the military hospital in Brest. It prospectively enrolled a cohort of all military asymptomatic patients under 40, without any underlying known heart condition. Military general practitioners listed, thanks to an anonymous form, the main features of the systolic murmur and of the ECG and proposed an auscultatory diagnosis: innocent or organic murmur. Then cardiologists did the same and finally performed a transthoracic echocardiography giving the diagnosis.

RESULTS

Fifty-eight patients were referred, 5 not meeting the inclusion criteria. Of the 53 patients included, military general practitioners found 46 innocent murmurs and 7 organic ones. Cardiologists found 51 innocent murmurs and 2 organic. Transthoracic echocardiography just took on one organic murmur (linked with a bicuspid aortic valve), spotted by the specialist, though judged innocent by the general practitioner.

DISCUSSION

Most of innocent murmurs diagnosed by general practitioners (45/46) were confirmed. Regarding the seven organic murmurs, the main selected criteria (intensity over 3, orthostatic persistence, diffuse irradiation) are mostly in accordance with the literature, proving right medical instincts. Authors propose a practical management of systolic murmurs among asymptomatic young patients.

CONCLUSION

Military general practitioners seem to master symptoms of organic murmur. This assessment argues for a promotion of a holistic clinical examination, which will help not only to rationalize the use of transthoracic echocardiography in economic terms but also to value the medical expertise.

Biomechanical evaluation of the pathophysiologic developmental mechanisms of mitral valve prolapse: effect of valvular morphologic alteration

Mitral valve prolapse (MVP) refers to an excessive billowing of the mitral valve (MV) leaflets across the mitral annular plane into the left atrium during the systolic portion of the cardiac cycle. The underlying mechanisms for the development of MVP and mitral regurgitation in association with MV tissue remodeling are still unclear. We performed computational MV simulations to investigate the pathophysiologic developmental mechanisms of MVP. A parametric MV geometry model was utilized for this study. Posterior leaflet enlargement and posterior chordal elongation models were created by adjusting the geometry of the posterior leaflet and chordae, respectively. Dynamic finite element simulations of MV function were performed over the complete cardiac cycle. Computational simulations demonstrated that enlarging posterior leaflet area increased large stress concentration in the posterior leaflets and chordae, and posterior chordal elongation decreased leaflet coaptation. When MVP was accompanied by both posterior leaflet enlargement and chordal elongation simultaneously, the posterior leaflet was exposed to extremely large prolapse with a substantial lack of leaflet coaptation. These data indicate that MVP development is closely related to tissue alterations of the leaflets and chordae. This biomechanical evaluation strategy can help us better understand the pathophysiologic developmental mechanisms of MVP.

Present role of the precordial examination in patient care

Recent observations suggest that many physicians do not consider the bedside cardiac examination as a valuable tool in patient care. Internists, hospitalists, emergency department physicians, cardiologists, physician assistants, and nurse practitioners were interviewed to ascertain their current practice in completing the cardiac examination. In addition, we surveyed patients in a cardiology practice concerning their attitudes about the cardiac physical examination. The study found that a significant number of practitioners failed to carry out a basic cardiac examination. Most patients do not have their chest exposed. It is unusual for the patient to be examined in the lateral decubitus position or for maneuvers to be used to evaluate the significance of a murmur. Most patients were more confident in the physician when a bedside examination was carried out, and they expect to undress for the examination. Half of the patients were more secure when they were undressed if there was a attendant of the same gender in the room. Review of the medical literature suggests that when a skilled examiner completes the bedside cardiac examination, it has an excellent sensitivity and specificity to recognize clinically significant cardiac disorders. A thorough cardiac bedside examination can make an echocardiogram unnecessary in some patients and compliment the echo in every patient. In conclusion, the bedside cardiac examination is a valuable diagnostic aid for diagnosing heart disease. If on the teaching wards and in the medical journals more emphasis is placed on the importance of physical findings for diagnosing heart disease, more physicians will make the effort to perform a thorough examination.

The Dutch experience of open access echocardiography

Cardiac disease is not easy to recognise in general practice. An echocardiogram is an excellent way to provide information about left ventricular mass and diastolic (dys)function and the presence of valvular heart disease. To improve diagnostic care of cardiac patients, an open access echocardiography service was established in the referral area of our hospital, where general practitioners were able to ask for an echocardiogram without referring the patient to the cardiologist. Between December 2002 and October 2006 echocardiograms were requested for 471 patients. Thirteen percent of the patients referred for dyspnoea and 3% of patients with a cardiac murmur had a left ventricular ejection fraction <40%. In 28% of patients no cardiac abnormality could be found. If we looked at the prevalence of hypertension in the referred patients, this was very high with a prevalence of up to 60% in the older age groups. If we included hypertension in the analysis, only 16% of patients had no structural cardiac or vascular abnormality. The study shows that the advantage of open access echocardiography in the Netherlands is that the general practitioner is able to make a better diagnosis and unnecessary referrals of patients with suspected cardiac disease can be avoided. (Neth Heart J 2007;15:342-7.).

Detection of innocent systolic murmurs by auscultation and their relation to hematologic and echocardiographic findings in clinically normal Whippets

OBJECTIVE

To determine murmur prevalence by auscultation of 105 apparently healthy Whippets without signs of cardiac disease, to determine the origin of these murmurs, and to evaluate the influence of sex, type of pedigree (ie, bred for showing or racing), and training on these murmurs.

DESIGN

Cross-sectional study.

ANIMALS

105 client-owned Whippets.

PROCEDURES

All dogs were auscultated by the first author and underwent a complete physical and cardiological examination, together with a hematologic assessment. Several RBC variables and echocardiographic variables were compared between dogs with or without a murmur at the level of the aortic valve.

RESULTS

44 of 105 (41.9%) dogs had no murmur. A soft systolic murmur was present with point of maximal intensity at the level of the aortic valve in 50 (47.6%) dogs, at the level of the pulmonic valve in 8 (7.6%) dogs, and at the level of the mitral valve in 3 (2.9%) dogs. No significant differences were found in heart rate, rhythm, murmur presence, point of maximal intensity, and murmur grade between males and females, between dogs with race- and show-type pedigrees, or between dogs in training and not in training. Dogs with a murmur at the level of the aortic valve had a significantly higher aortic and pulmonic blood flow velocity and cardiac output, compared with dogs without a murmur.

CONCLUSIONS AND CLINICAL RELEVANCE

Whippets have a high prevalence of soft systolic murmurs in the absence of any structural abnormalities, which fit the description of innocent murmurs. No influence of sex, pedigree type, or training was found on the occurrence of these murmurs in Whippets.

Prevalence of echocardiographic evidence of cardiac disease in apparently healthy cats with murmurs

The objective of this prospective study was to determine the prevalence of echocardiographic evidence of heart disease in apparently healthy cats with heart murmurs. Thirty-two privately owned domestic cats were examined. All cats were considered healthy on the basis of history and physical examination, except for the finding of a heart murmur on auscultation. Cats on any medications (besides regular flea, tick and heartworm preventative) or that were pregnant or lactating were excluded from this study. The prevalence of echocardiographic evidence of heart disease in this population of cats was 53%. Therefore, identification of a heart murmur on routine physical examination in apparently healthy cats warrants further investigation.

Focused Transthoracic Echocardiography in the Perioperative Period

Ultrasound applications in perioperative medicine have expanded enormously over the past decade. Transoesophageal echocardiography has been performed by anaesthetists during cardiac surgery for over 20 years. With the increasing availability of portable ultrasound systems, the use of ultrasound to assist in vascular cannulation and regional anaesthesia has been well described. Portable ultrasound systems come with a range of probes for different applications, including transthoracic echocardiography. While transthoracic echocardiography has traditionally been the domain of cardiologists, its use has been increasing in critical care, the emergency room and, recently, by anaesthetists in the perioperative period. Unlike formal cardiology-based transthoracic echocardiography, focused, goal-directed transthoracic echocardiography is often more appropriate in the perioperative period to address a particular question and can be performed in just a few minutes. Transthoracic echocardiography allows rapid, noninvasive, point-of-care assessment of ventricular function, valvular integrity, volume status and fluid responsiveness. It can help distinguish undifferentiated systolic murmurs preoperatively, give valuable information on the aetiology of unexplained hypotension and cardiovascular collapse and assess response to therapeutic interventions such as vasoactive drugs and volume resuscitation. Focused transthoracic echocardiography should include qualitative assessment of left and right ventricular function, an estimate of aortic valve gradient, right ventricular systolic pressure and intravascular volume status as minimum requirements. Transthoracic echocardiography is a valuable tool in the perioperative period and ideally the equipment and expertise should be available in all operating rooms.

The development of a new cardiac auscultation test: How do screening and diagnostic skills differ?

BACKGROUND

Newly qualified doctors are expected to be able to conduct a cardiac auscultation unassisted, but studies show conflicting results regarding cardiac auscultation skills.

METHODS

A two-part test instrument was designed containing innovative recordings of heart sounds from patients with common cardiac murmurs as well as healthy controls. A total number of 109 participants were tested, representing four levels of clinical experience. The content validity of the test instrument was studied by a postal questionnaire to 114 clinical teachers at the University Hospital of Aarhus, Denmark.

RESULTS

A significant correlation was found between level of experience and the ability to diagnose the conditions from which the murmurs originated (r = 0.45, P < 0.0001). No correlation was found between level of experience and the ability to identify persons with cardiac murmurs from healthy controls. All groups showed a tendency to interpret healthy heart sounds as cardiac murmurs.

CONCLUSIONS

Diagnostic ability was found to correlate positively with clinical experience, whereas the ability to distinguish cardiac murmurs from normal heart sounds seems independent of clinical experience.

Heart murmur and N-terminal pro-brain natriuretic peptide as predictors of death in 2977 consecutive hospitalized patients

BACKGROUND

Little is known about the prognostic importance of murmur in unselected patients. It is difficult to distinguish between innocent and significant murmurs. N-terminal pro-brain natriuretic peptide (NT-pro-BNP) and BNP have recently been shown to be useful in small series of patients with valvular heart disease. We wanted to test whether murmur predicts mortality in unselected patients admitted to the hospital and whether NT-pro-BNP is capable of distinguishing between innocent and significant murmurs.

METHODS

Consecutive patients (n = 2977) older than 40 years admitted to a local hospital were studied. Auscultation, echocardiography were performed and levels of natriuretic peptides were measured.

RESULTS

A total of 21.8% of the 2977 patients had a murmur. After adjusting for sex and age there was a significant difference in the one-year mortality of patients with and without murmur (OR = 1.57, 95% CI = 1.27-1.94). NT-pro-BNP gave additional prognostic information for both patients with and without murmurs. Presence of a murmur was an independent predictor of 1-year mortality (OR = 1.36, 95% CI = 1.03-1.80) in a multivariate analysis. In patients with a murmur but normal NT-pro-BNP, discovery of valvular heart disease by echocardiography yielded no additional prognostic information.

CONCLUSIONS

Detection of a cardiac murmur during routine medical examination of hospitalized patients is associated with increased risk of death within a year. A blood test for NT-pro-BNP gives significant additional prognostic information of a murmur and could obviate the need for echocardiography in selected patients with a murmur and normal NT-pro-BNP for whom surgery is not feasible.

Burden of valvular heart diseases: a population-based study

BACKGROUND

Valvular heart diseases are not usually regarded as a major public-health problem. Our aim was to assess their prevalence and effect on overall survival in the general population.

METHODS

We pooled population-based studies to obtain data for 11 911 randomly selected adults from the general population who had been assessed prospectively with echocardiography. We also analysed data from a community study of 16 501 adults who had been assessed by clinically indicated echocardiography.

FINDINGS

In the general population group, moderate or severe valve disease was identified in 615 adults. There was no difference in the frequency of such diseases between men and women (p=0.90). Prevalence increased with age, from 0.7% (95% CI 0.5-1.0) in 18-44 year olds to 13.3% (11.7-15.0) in the 75 years and older group (p<0.0001). The national prevalence of valve disease, corrected for age and sex distribution from the US 2000 population, is 2.5% (2.2-2.7). In the community group, valve disease was diagnosed in 1505 (1.8% adjusted) adults and frequency increased considerably with age, from 0.3% (0.2-0.3) of the 18-44 year olds to 11.7% (11.0-12.5) of those aged 75 years and older, but was diagnosed less often in women than in men (odds ratio 0.90, 0.81-1.01; p=0.07). The adjusted mortality risk ratio associated with valve disease was 1.36 (1.15-1.62; p=0.0005) in the population and 1.75 (1.61-1.90; p<0.0001) in the community.

INTERPRETATION

Moderate or severe valvular diseases are notably common in this population and increase with age. In the community, women are less often diagnosed than are men, which could indicate an important imbalance in view of the associated lower survival. Valve diseases thus represent an important public-health problem.

A hand-carried cardiac ultrasound device in the outpatient cardiology clinic reduces the need for standard echocardiography

OBJECTIVE

To assess the potential value and cost-effectiveness of a hand-carried ultrasound (HCU) device in an outpatient cardiology clinic.

METHODS

222 consecutive patients were prospectively enrolled in the study. When standard echocardiography (SE) was specifically indicated on the basis of clinical history, electrocardiogram and physical examination, the same cardiologist (level-2 or level-3 trained) immediately performed an HCU examination. The cardiologist then reassessed the clinical situation to confirm or cancel the SE request according to the information provided by HCU. The SE examination was performed by a sonographer and examined in a blinded fashion by a cardiologist expert in echocardiography. Findings from the two examinations were compared.

RESULTS

HCU was performed in 108/222 patients, and a definite diagnosis was established in 34 of them (31%), making SE examination potentially avoidable. In the 74 patients with inconclusive HCU results and for whom SE was still indicated, the decision was mainly dictated by the lack of spectral Doppler modality in the HCU system. The overall agreement between HCU and SE for diagnosis of normal/abnormal echocardiograms was 73% (kappa = 0.4). On the basis of the potentially avoided SE examinations and the obviated need for a second cardiac consultation, a total cost saving of euro2142 per 100 patients referred for echocardiography was estimated.

CONCLUSIONS

The use of a simple HCU device in the outpatient cardiology clinic allowed reliable diagnosis in one third of the patients referred for echocardiography, which translates into cost and time saving benefits.

Effect of teaching and type of stethoscope on cardiac auscultatory performance

BACKGROUND

Auscultation of the heart is a routine procedure. It is not known whether auscultatory skills can be improved by teaching or with the use of an advanced stethoscope.

METHODS

This study was a randomized trial with a 2 x 2 factorial design. Seventy-two house officers were randomized to a simple or an advanced stethoscope and to a 4-hour course in auscultation or no course. The doctors auscultated 20 patients' hearts and categorized findings as normal or as one or more of 5 categories of heart diseases. Patients were selected such that 16 had a known heart disease as well as a corresponding murmur and 4 had no heart disease or murmur. Auscultatory performance was assessed as concordance with echocardiographic findings and interobserver variation.

RESULTS

Doctors using the advanced stethoscope diagnosed 35% of the patients correctly, as compared with doctors using the simple stethoscope who did 33% of the patients (P = .27). Similarly, 34% of the patients were diagnosed correctly by doctors who had received teaching as compared with 33% of those who were by doctors who had received no teaching (P = .41). The kappa values were higher for doctors who had received teaching for aortic stenosis (0.43 vs 0.28, P = .004) and ventricular septum defect (0.07 vs 0.01, P = .003). There was no difference between groups for any other single murmur or for the detection of murmurs as such.

CONCLUSION

Heart auscultation findings were in poor accordance with echocardiographic findings and had high interobserver variation. Neither outcome improved to any important extent with the subjects' use of an advanced stethoscope or attending of a course in heart auscultation.

Easy Access Echocardiography for the General Practicioner: Results from the Parkstad Area in The Netherlands

Heart failure has a low incidence in general practice but is not easy to recognize in this setting. Frequently a normal electrocardiogram and a normal level of brain natriuretic peptide can exclude heart failure as a cause for dyspnea. Unfortunately the positive predictive value of both techniques is low. Imaging with echocardiography can then give the clue to the correct diagnosis. Also correct diagnosis of cardiac murmurs is not easy in general practice. Therefore an open access echocardiographic service was established in the south of the Netherlands. According to the existing services in the United Kingdom general practitioners in this area were able to ask for an echocardiogram without referring the patient to the cardiologist. During a period of 19 months 131 patients were referred to the Centre of Medical Diagnostics for an echocardiogram. In 12% of the patients referred for dyspnea a left ventricular ejection fraction lower than 40% was found. Fourty nine percent of the patients had diastolic dysfunction. In 33% heart failure could be excluded. In 62% of the patients referred for a cardiac murmur cardiac pathology could be found. In 38% of the patients the cardiac murmur could be established as a functional murmur. The service was found to improve practice by most of the general practitioners.

Comparison of effectiveness of hand-carried ultrasound to bedside cardiovascular physical examination

This study compared the accuracy of cardiovascular diagnoses by medical students operating a small hand-carried ultrasound (HCU) device with that of board-certified cardiologists using standard physical examinations. Sixty-one patients (38% women; mean age 70 +/- 19 years) with clinically significant cardiac disease had HCU studies performed by 1 of 2 medical students with 18 hours of training in cardiac ultrasound and physical examinations by 1 of 5 cardiologists. Diagnostic accuracy was determined by standard echocardiography. Two-hundred thirty-nine abnormal findings were detected by standard echocardiography. The students correctly identified 75% (180 of 239) of the pathologies, whereas cardiologists found 49% (116 of 239) (p <0.001). The students' diagnostic specificity of 87% was also greater than cardiologists' specificity of 76% (p <0.001). For nonvalvular pathologies (115 findings), students' sensitivity was 61%, compared with 47% for cardiologists (p = 0.040). There were 124 clinically significant valvular lesions (111 regurgitations, 13 stenoses). Students' and cardiologists' sensitivities for recognizing lesions that cause a systolic murmur were 93% and 62% (p <0.001), respectively. Students' sensitivity for diagnosing lesions that produce a diastolic murmur was 75%; cardiologists recognized 16% of these lesions (p <0.001). The diagnostic accuracy of medical students using an HCU device after brief echocardiographic training to detect valvular disease, left ventricular dysfunction, enlargement, and hypertrophy was superior to that of experienced cardiologists performing cardiac physical examinations.

Appreciation of Precordial Cardiac Murmur on Examination Relative to Knowledge of Valvular Heart Disease

Skills associated with physical examination have continued to decline as practitioners have become increasingly reliant on advanced imaging modalities. Our study sought to determine if documentation of valvular heart disease on echocardiography resulted in an increased appreciation and documentation of precordial murmur.

The patient with a heart murmur: evaluation, assessment and dental considerations

BACKGROUND

Heart murmurs, a common finding in dental patients, are of major concern to dental professionals because certain dental procedures occasionally can induce severe cardiovascular complications. Murmurs may indicate existing heart disease that is a risk factor for infective endocarditis following a dental procedure, as well as more severe heart conditions such as congenital heart disease, atrial fibrillation or congestive heart failure.

TYPES OF STUDIES REVIEWED

This review article is based on data published in peer-reviewed journals, including practice guidelines published by major dental and medical professional organizations.

RESULTS

Echocardiography is the primary means of evaluating heart murmurs, and all dental professionals should become familiar with major aspects of an echocardiogram. Understanding the medical evaluation and assessment of a heart murmur fosters better communication with other health care professionals and results in improved patient care.

CLINICAL IMPLICATIONS

Beyond the need to administer antibiotic prophylaxis, the dentist also needs to address the underlying causes of a patient's heart murmur. By providing dental care to such patients, oral health care providers become part of the patient's overall health care team.