Austin Flint Murmur Research Articles

Insights into mechanisms of the Austin Flint murmur: learning from 2D and 3D echocardiography.

Insights into mechanisms of the Austin Flint murmur: learning from 2D and 3D echocardiography.

422 Transoesophageal Echocardiography in Diagnosing Acute Aortic Dissection not Evident on CT Aortogram

CT aortogram is considered the gold-standard for diagnosing acute aortic dissection, but false-negative studies can occur. A 43-year-old male presented with sharp central chest pain radiating to his neck with associated dyspnoea, a viral prodrome and low-grade temperature (37.4°C). There was no documented blood pressure differential or audible murmur, ECG was unremarkable, and troponin-T was mildly elevated (22ng/L). CT pulmonary angiogram showed no pulmonary embolism, and a transthoracic echocardiogram (TTE) with suboptimal image quality indicated normal left ventricular (LV) size and systolic function, normal aorta size, mild aortic regurgitation (AR) and a small pericardial effusion. He was treated for suspected pericarditis, however developed acute kidney injury and acute pulmonary oedema requiring admission for ten days. He re-presented three days later with worsening dyspnoea, and a repeat transthoracic echocardiogram showed severe LV dilatation, dilated aortic root (45mm) and severe AR. An ECG-gated CT aortogram showed no evidence of aortic dissection. A transoesophageal echocardiogram (TOE) was performed to exclude endocarditis, and showed a Type A aortic dissection, dilated ascending aorta (48mm) and severe AR. He urgently underwent successful mechanical Bentall’s repair. This is an atypical presentation of acute aortic dissection diagnosed two weeks after initial presentation, with the dissection flap clearly visualised on TOE but not evident on CT aortogram. In retrospect, M-mode on the initial TTE identified fluttering of the anterior mitral valve leaflet consistent with an Austin-Flint murmur, and pulsed-wave Doppler indicated elevated stroke volume consistent with acute severe AR which was underappreciated on colour-flow Doppler.

A Simulator-Based Study of In-Flight Auscultation

The use of a stethoscope is essential to the delivery of continuous, supportive en route care during aeromedical evacuations. We compared the capability of 2 stethoscopes (electronic, Litmann 3000; conventional, Litmann Cardiology III) at detecting pathologic heart and lung sounds, aboard a C135, a medical transport aircraft. Sounds were mimicked using a mannequin-based simulator SimMan. Five practitioners examined the mannequin during a fly, with a variety of abnormalities as follows: crackles, wheezing, right and left lung silence, as well as systolic, diastolic, and Austin-Flint murmur. The comparison for diagnosis assessed (correct or wrong) between using the electronic and conventional stethoscopes were performed as a McNemar test. A total of 70 evaluations were performed. For cardiac sounds, diagnosis was right in 0/15 and 4/15 auscultations, respectively, with conventional and electronic stethoscopes (McNemar test, P = 0.13). For lung sounds, right diagnosis was found with conventional stethoscope in 10/20 auscultations versus 18/20 with electronic stethoscope (P = 0.013). Flight practitioners involved in aeromedical evacuation on C135 plane are more able to practice lung auscultation on a mannequin with this amplified stethoscope than with the traditional one. No benefit was found for heart sounds.

Altered Mitral Inflow Orifice in Severe Aortic Regurgitation: Real Time Three-Dimensional Echocardiographic Findings

We present the case of a young man with severe eccentric aortic regurgitation, obstructing mitral inflow and provoking an audible Austin Flint murmur at clinical examination. Two-dimensional color Doppler echocardiography depicts the remarkable mechanical interaction between aortic regurgitant jet and anterior mitral leaflet opening. Three-dimensional transesophageal echocardiography aids in understanding the geometric and hemodynamic consequences of the regurgitant jet and in the genesis of the Austin Flint murmur. This case accentuates the incremental value of three-dimensional echocardiography when evaluating valvular pathology, and offers more insight in the interaction between aortic regurgitant flow and mitral leaflet dynamics.

Name That Murmur — Eponyms for the Astute Auscultician

After the introduction of the stethoscope by Rene Laennec in 1819, the art of auscultation gained traction as a group of early adopters described the heart murmurs they were now able to hear. A race to discover and define ensued. Leading physicians published their new observations, and a robust crop of eponyms was born for use by future generations of physicians and medical trainees. This list of eponymous heart murmurs includes a number of particularly esoteric selections that should satisfy novices and seasoned clinicians alike. Austin Flint Murmur Austin Flint was an American physician practicing in the early and middle . . .

Feeling the Pressure? Anterior Mitral Leaflet Immobility in a Patient With Bicuspid Aortic Valve Disease

A 32-YEAR-OLD, 87-kg, 173-cm man with a past medical history of a congenital bicuspid aortic valve was admitted to the authors' hospital for evaluation of dyspnea on exertion. The patient had been a frequent participant in strenuous athletic activities including full-court basketball. He reported that his stamina during these activities had declined substantially in recent months. The patient also described unusual episodes of fatigue while performing his job as a biomedical engineer. He denied a history of angina pectoris, syncope, palpitations, orthopnea, paroxysmal nocturnal dyspnea, and peripheral edema. The physical examination was notable for a grade III of VI holodiastolic murmur heard best along the left sternal border. An Austin Flint murmur 1 Flint A. On cardiac murmurs. Am J Med Sci. 1862; 44: 29-54 Google Scholar was not appreciated. The remainder of the physical examination was noncontributory. Noninvasive measurements of arterial blood pressure indicated the presence of a widened pulse pressure (75-80 mmHg). A plasma brain natriuretic peptide concentration was normal. Transesophageal echocardiography (TEE) was performed as part of the evaluation and confirmed the presence of a bicuspid aortic valve with thickened anterior-lateral (left and right coronary cusp fusion; type A) 2 Russo C.F. Cannata A. Lanfranconi M. et al. Is aortic wall degeneration related to bicuspid aortic valve anatomy in patients with valvular disease?. J Thorac Cardiovasc Surg. 2008; 136: 937-942 Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar and posterior-medial leaflets of approximately equal size. The TEE examination also revealed that the middle scallop of the anterior mitral leaflet (A2) was essentially immobile throughout the cardiac cycle (Fig 1, Fig 2 and Video 1 [supplementary videos are available online]). What is the cause of this anterior mitral leaflet immobility? Fig 2The midesophageal long-axis view obtained during early diastole; the location and shape of the middle scallop of the anterior mitral leaflet (A2) are essentially unchanged compared with Figure 1. View Large Image Figure Viewer Download Hi-res image

Austin Flint murmur re-visited

Austin Flint murmur is a mid-diastolic rumbling audible in subjects with severe aortic regurgitation. Several theories have been raised to explain mechanistically the nature of this particular phenomenon. We briefly review severe aortic regurgitation under the light of contemporary echocardiography in an illustrative case.

Cardiac pearls

Most diagnoses of cardiovascular disease are made in the office or at the bedside. For example, in pulsus alternans of the radial pulse, observed when first greeting a patient, alteration of intensity of the second sound and systolic murmur and a ventricular (S3) gallop are clinical pearls--often subtle--that diagnose cardiac decompensation. A faint gallop, ventricular (S3) or atrial (S4), might be overlooked in a patient who has an emphysematous chest and an increase in anteroposterior diameter if one listens over the usual areas of the precordium. However, the gallop might be detected easily by listening over the xiphoid or epigastric area. How do you tell the difference between an S4, a split first sound, and an ejection sound? The S4 is eliminated with pressure on the stethoscope, but pressure does not eliminate the ejection sound or the splitting of S1. The atrial sound (S4) is most frequently found in patients who have coronary heart disease, and it is a constant finding in patients who have hypertension. It does not denote heart failure, as does the S3 (ventricular) gallop. In some patients, both atrial (S4) and ventricular (S3) diastolic gallops may be present. This occurrence is common in patients with cardiac decompensation associated with coronary heart disease, hypertensive heart disease, and dilated cardiomyopathy. When these diastolic filling sounds occur in close proximity, a short rumbling murmur may be heard, which causes confusion of this sound with that of a valvular or congenital lesion. When both sounds occur exactly simultaneously, a single sound results. Often, this sound is louder than either the first or second sound and can be misinterpreted as either a valvular or congenital lesion. This, however, is a summation gallop, which is rare. For the most accurate timing of heart sounds and murmurs, the simple technique called "inching" is the best. Keeping the second sound in mind as a reference, the physician moves (inches) the stethoscope from the aortic area to the apex. An extra sound may be noted to occur in systole before the second sound, thereby diagnosing a systolic click. If the sound occurs after the second sound, however, it is an S3 or ventricular diastolic gallop. If a murmur appears before S2, it is a systolic murmur; if it appears after S2, it is a diastolic murmur. When the Austin-Flint murmur is heard, significant aortic regurgitation exists.(ABSTRACT TRUNCATED AT 400 WORDS)

Genesis of the austin flint murmur: Relation to mitral inflow aortic regurgitant flow dynamics

Objectives. This study was designed to elucidate the genesis of the Austin Flint murmur.Background. The Austin Flint murmur is an apical diastolic rumble associated with significant aortic regurgitation. The precise mechanism of the murmur remains unclear.Methods. The relation between the Austin Flint murmur and mitral inflow and aortic regurgitant flow dynamics was evaluated nonivasively in 13 patients with moderate to severe aortic regurgitation and 15 control subjects using phonocardiographic and pulsed and color-coded Doppler echocardiographic techniques. The severity of aortic regurgitation was determined by color-coded Doppler echocardiography on the basis of the maximal distance of the regurgitant signal.Results. The direction of aortic regurgitant flow was unrelated to the presence of the Austin Flint murmur. The severity of aortic regurgitation was greater in patients with than in those without this murmur. The peak mitral inflow velocity during early diastole (E) was significantly increased, and both peak mitral inflow velocity at atrial contraction (A) and the A/E ratio were significantly decreased in patients with the Austin Flint murmur compared with values in those without this murmur or in control subjects. However, the maximal amplitude of the Austin Flint murmur did not coincide temporally with the peak mitral inflow velocity. The murmur continued both after rapid mitral inflow had ended and during diastolic mitral regurgitation.Conclusions. The increased velocity of early diastolic mitral inflow in patients with the Austin Flint murmur is due to aortic regurgitation, but rapid mitral inflow is not an essential requirement for production of the murmur. In some cases, the Austin Flint murmur may be generated by aortic regurgitant flow alone.

Etiology of the Austin Flint Murmur

Objectives. The aim of the study was to determine the mechanism of the Austin Flint murmur. Background. More than 100 years after the initial description of the Austin Flint murmur, the etiology of the murmur remains unclear.Methods. M-mode and two-dimensional echocardiography, conventional and color flow Doppler study, and cine nuclear magnetic resonance (cine NMR) imaging were performed in 24 patients with clinically moderate or severe aortic regurgitation. Mitral valve area was determined by planimetry and pressure half-time measurement. Overlap of the aortic regurgitation and mitral inflow jets was graded 0 (no overlap) to 4 (marked overlap) by Doppler study and cine NMR imaging. The volume of signal loss resulting from turbulent blood flow secondary to the aortic regurgitation jet was determined on cine NMR images, and the extent of contact with the left ventricular endocardium was graded 0 (no contact) to 4 (extensive contact).Results. The presence of an Austin Flint murmur did not correlate with mitral valve area (2.7 ± 0.8 cm2with the murmur vs. 2.5 ± 0.7 cm2without), overlap of the aortic regurgitation and mitral inflow jets (3 ± 1 vs. 2.3 ± 1.2), diastolic mitral regurgitation (50% vs. 71%) or fluttering of the anterior mitral valve leaflet (70% vs. 50%). The presence of an Austin Flint murmur correlated best with the volume of signal loss associated with the aortic regurgitation jet on cine NMR imaging (65 ± 16 ml with the murmur, vs. 38 ± 11 ml without, p < 0.001) and the extent of contact of this signal loss with the left ventricular endocardium (2.9 ± 0.5 vs. 1.5 ± 0.4, p < 0.0001).Conclusions. The Austin Flint murmur is caused by the aortic regurgitation jet abutting the left ventricular endocardium, resulting in the generation of a low-pitched diastolic rumbling.

Doppler and echocardiographic characteristics of patients having an Austin Flint murmur.

The purpose of this study was to investigate the genesis of the Austin Flint murmur using Doppler and echocardiographic imaging. A total of 51 patients having significant aortic insufficiency and an anatomically normal mitral valve were evaluated. They were divided into two groups; 30 patients had an audible Austin Flint murmur (AFM+) and 21 did not (AFM-). All patients had a complete M-mode, two-dimensional, and Doppler echocardiographic examination to characterize left ventricular size and function, motion of the mitral valve, transmitral flow velocities, direction of the aortic insufficiency jet, and severity of aortic insufficiency. There was no significant difference in severity of aortic insufficiency between groups. There was, however, a significant difference in direction of the insufficiency jet. In the AFM+ group compared with the AFM- group, for the parasternal long-axis view 24 (80%) versus eight (38%) had their insufficiency jet directed at the mitral valve, for the apical five-chamber view the values were 25 (83%) versus five (24%), and for the apical long-axis view the values were 27 (90%) versus five (24%); for all comparisons p less than 0.01. There was also a greater frequency of localized anterior mitral leaflet distortion by two-dimensional echocardiography (AFM+:23 [77%] versus AFM-:five [24%]; p less than 0.001) and a greater frequency of Doppler striations overlying the aortic insufficiency jet (AFM+:25 [83%] versus AFM-:seven [33%]; p less than 0.001). Regarding transmitral flow velocities, there was no significant difference in filling patterns or absolute velocities during early or late diastole between groups. There was no gradient by Doppler analysis or by hemodynamics (n = 26) across the mitral valve in either group. There also was no difference in the frequency of preclosure of the mitral valve (AFM+:two versus AFM-:three). Systolic function was similar in both groups, but the left ventricular end-diastolic dimension was significantly greater in the AFM+ group (6.8 +/- 0.8 cm) than in the AFM- group (6.2 +/- 0.7 cm, p = 0.008). The results of this study suggest that the primary factor responsible for the Austin Flint murmur is the presence of an aortic insufficiency jet directed at the anterior mitral leaflet. This, combined with the biphasic pattern of transmitral flow, distorts the shape of the anterior mitral leaflet as it opens and closes during diastole, making it shudder. The leaflet's shuddering sets up vibrations and shock waves that distort the aortic insufficiency jet, causing the observed Doppler striations and probably the sound of the murmur. There is no evidence from this study to support prior theories that have proposed functional mitral stenosis or diastolic mitral regurgitation as the source of the murmur.

Familial Dissecting Aortic Aneurysm in the Absence of Marfan's Syndrome with Review of the Literature: Case Report

This is a report of familial aortic dissection in a mother and son with no evidence of Marfan's syndrome in either patient. The mother, a fifty-three—year-old nurse, was evaluated initially for a four-year history of untreated hypertension and heart murmurs. Multiple cardiac complaints, including shortness of breath and chest pain on exertion, with a strong smoking history associated with an Austin-Flint murmur were noted. Subsequent laboratory studies, including electrocardiogram and cardiac catheterization, confirmed the diagnosis of dissection in the ascending aorta with free communication with an aneurysmal sac. Operative intervention included a Dacron prosthesis and porcine xenograft for aortic valve replacement. The postoperative course is unremarkable and the patient remains well after eleven years. Her twenty- eight-yearold son had a heart murmur identified on an office visit for a recurrent upper respiratory infection. Increased symptoms of shortness of breath, pulsus bisferiens, and an Austin-Flint murmur, along with findings on electrocardiogram and subsequent cardiac catheterization, confirmed the diagnosis of dissecting aortic aneurysm. The patient did not tolerate surgical intervention and a supraventricular tachycardia resulted in his death. Autopsy confirmed the extent of dissection, a 630-g heart with biventricular dilatation, hypertrophy, and dilatation of the atria; there was extensive cystic medial necrosis in the aorta. Marfan's syndrome is excluded because of the genetic predisposition to dissecting aortic aneurysm and no other findings of the Marfan's syndrome were identified. This report is to document the genetic predisposition and identification of 2 cases of congenital aortic dissection and its consequences.

Physiologic mechanisms in aortic insufficiency. I. The effect of changing heart rate on flow dynamics. II. Determinants of Austin Flint murmur.

We studied the dynamic changes in mitral flow patterns and in mitral valve motion before and after producing acute, reversible aortic insufficiency (AI) in nine open-chest dogs. Phasic mitral flow, the mitral valve echocardiogram, and intracardiac phonocardiogram and other hemodynamic variables were measured. During moderate AI (mean regurgitant fraction 52 +/- 5%) (+/- SD), the antegrade filling volume decreased from 31 +/- 7 to 24 +/- 6 ml (p less than 0.01), but the peak protodiastolic mitral flow rate increased from 139 +/- 37 to 157 +/- 42 ml/sec (p less than 0.01), reflecting the shift of a larger fraction of total mitral filling volume to early diastole. In six dogs, atrial pacing was used to examine the hemodynamic effects of tachycardia. Increasing the heart rate from 90 to 120 beats/min increased cardiac output from 2.64 +/- 0.56 to 3.3 +/- 0.831/min (p less than 0.05) and decreased left atrial pressure from 24 +/- 8 to 17 +/- 7 mm Hg (p less than 0.05). Increasing heart rate to 150 beats/min compromised mitral filling, reduced cardiac output and increased left atrial pressure. Moderate tachycardia improves cardiac performance in AI by reducing regurgitant volume, without significantly reducing transmitral filling volume. The mitral valve echocardiogram showed only a small decrease in cusp opening amplitude during AI. A low-pitched left ventricular inflow tract murmur was recorded in protodiastole and corresponded in time to the rapidly increasing mitral flow. We conclude that the major determinant of the turbulence responsible for the creation of the austin flint murmur is the antegrade mitral flow stream and its mixing with the retrograde aortic flow.

The effect of acute aortic insufficiency on the dynamics of mitral valve motion and instantaneous trans-mitral flow: Hemodynamic mechanism for the austin flint murmur

The effect of acute aortic insufficiency on the dynamics of mitral valve motion and instantaneous trans-mitral flow: Hemodynamic mechanism for the austin flint murmur

Clinical study on the right-sided Austin Flint murmur using intracardiac phonocardiography

Right heart catheterization was carried out on 14 patients with pulmonic regurgitation using intracardiac phonocardiography. All the patients showed pulmonic regurgitant murmur in the right ventricular outflow tract. In addition, seven out of the 14 patients showed mid-diastolic and presystolic murmurs maximally in the inflow tract of the right ventricle. Furthermore, inspiration increased the loudness of these diastolic murmurs in four patients. These findings were compatible with those of right-sided Austin Flint murmur due to functional tricuspid stenosis in pulmonic incompetence. Ten out of the 14 patients had pulmonary hypertension and all the subjects with a right-sided Austin Flint murmur showed elevated pulmonary arterial pressure. Thus, pulmonic regurgitation with pulmonary hypertension is thought to be closely related to the right-sided Austin Flint murmur and the turbulence resulting from antegrade flow across a closing tricuspid valve may be responsible for the genesis of this murmur.

Oscillation of left ventricular structures in aortic regurgitation

High-frequency diastolic oscillation of the anterior mitral leaflet is a common echocardiographic feature in aortic regurgitation. We have studied a group of 56 patients with aortic regurgitation in whom oscillation of the anterior mitral leaflet was present. Thirty-one of these had similar diastolic oscillation of the posterior leaflet; occasional patients demonstrated oscillation of the interventricular septum or chordae tendineae. The presence of these diastolic oscillations did not correlate with the presence of the Austin-Flint murmur. We conclude that diastolic oscillation of left ventricular structures other than the anterior mitral leaflet can be recorded on echocardiograms of patients with aortic regurgiationmthe mechanism responsible for these oscillations is not known; several possibilities are discussed.

Late Mitral Valve Opening in Aortic Regurgitation

Austin Flint first described the occurrence of an apical diastolic rumble in patients with severe aortic regurgitation. 1 Flint A On cardiac murmurs. Am J Med Sci. 1886; 91: 27 Crossref Google Scholar With the advent of echocardiography, mid and late mitral valve closure have been demonstrated in some patients with this murmur. 2 Fortuin NJ Craige EP On the mechanism of the Austin Flint murmur. Circulation. 1972; 45: 558 Crossref PubMed Scopus (48) Google Scholar , 3 DeMaria AN King JF Salel AF et al. Echography and phonography of acute aortic regurgitation in bacterial endocarditis. Ann Intern Med. 1975; 82: 329-335 Crossref PubMed Google Scholar The reverse situation, early mitral valve closure with late mitral valve opening, has been described less frequently.

Sound pressure correlates of the Austin Flint murmur. An intracardiac sound study.

Mitral valve motion and pressure correlates of the Austin Flint murmur (AFM) were investigated in nine patients with aortic regurgitation using high fidelity catheter tip micromanometers and the mitral valve echocardiogram (MVE). External phonocardiography demonstrated a mid-diastolic murmur (MDM) in eight subjects and a presystolic murmur (PSM) in five. Maximum intensity of both AFM components was found in the left ventricular (LV) inflow tract; the murmur was not recordable in the left atrium (LA). In two patients, an apparent AFM was recorded in the intracardiac phonocardiogram when absent externally. Only one subject had a significant late diastolic "reversed" or LV to LA gradient; in this patient, presystolic mitral regurgitation was shown angiographically but no PSM was present and MVE revealed absence of atriogenic mitral valve re-opening. In two subjects, a PSM disappeared from the external phono when a "reversed" gradient occurred during the diastolic pause following a ventricular premature systole; this LV to LA gradient was associated with diastolic mitral regurgitation recordable in the left atrial phono. In two patients, LV inflow phono showed the MDM to begin 80-120 msec after the aortic second sound and during the D to E phase of the MVE. The rate of early diastolic mitral valve closure in patients (152 +/- 24 mm/sec) was not significantly different from 13 normals (232 +/- 10 mm/sec). With regard to the genesis of the AFM, the present study concludes: 1) diastolic mitral regurgitation plays no role, and 2) antegrade mitral valve flow is required but simultaneous retrograde aortic flow may also be necessary.

Diastolic murmurs in the presence of Starr-Edwards mitral prosthesis.

Diastolic murmurs associated with the Starr-Edwards mitral prosthesis have not been described previously. In this report, five patients with mitral prostheses are described in whom apical mid-diastolic and presystolic murmurs resulted from two different causes. Three patients had clots obstructing the prosthetic orifice. The other two had normally functioning protheses and moderately severe aortic insufficiency. The occurrence of mid-diastolic and presystolic murmurs in the presence of a normally functioning prosthetic mitral valve demonstrates that 1) the mid-diastolic Austin Flint murmur can occur in the absence of incomplete mitral valve opening, premature mitral valve closure, vibrating mitral leaflets, or relative mitral stenosis and 2) the presystolic Austin Flint murmur can occur in the absence of incomplete valve opening or presystolic mitral regurgitation. However, the presystolic murmur was associated with early closure movement of the presthetic poppet.

Right-sided austin flint murmur: Documentation by intracardiac phonocardiography, echocardiography and postmortem findings

A 25 year old man with multiple congenital cardiac defects, pulmonary hypertension, pulmonary reguritation had a loud mid-diastolic rumbling murmur with presystolic accentuation, heard best at the lower left sternal border and cardiac apex. Intracardiac and external phonocardiograms, echocardiograms and postmortem findings documented that the rumble represented a “right-sided Austin Flint” murmur.