DYNAMIC AUSCULTATION FOR CARDIAC MURMURS Dr. Benny J. Panakkal Senior Resident Dept. of Cardiology Govt. Medical College Kozhikode.

RESPIRATORY VARIATION MULLER MANEUVER VALSALVA MANEUVER SUSTAINED HANDGRIP POSTURAL CHANGES POST – VPC / LONG DIASTOLE OF AF PHARMACOLOGICAL MANEUVERS – AMYL NITRITE PRESENTATION OUTLINE 23-11-2018

RESPIRATORY VARIATION 23-11-2018

RESPIRATORY VARIATION INSPIRATION 1. Normal inspiration → dilatation of pulmonary vascular system and ↑ venous return to right side of the heart → frank-starling mechanism → ↑ stroke volume 2. ↑ stroke volume also aided by ↓ RV outflow impedance 3. Respiratory variation most marked in sitting and standing position 4. Normal or slightly deep breaths allowed. Very deep respirations → Partial Valsalva phenomenon RESPIRATORY VARIATION Muller's is exaggerated normal respiration 23-11-2018

RESPIRATORY VARIATION MULLER MANOEUVRE Methods to elicit Close nose with finger in mouth → suck the finger with closed glottis Suck on a mouthpiece hooked to mercury manometer for 10 secs at 40-50 mm Hg negative pressure Increases right heart flow for longer periods compared to respiration All right sided events ↑ with inspiration Except pulmonary ejection click RESPIRATORY VARIATION 23-11-2018

PULMONARY EJECTION CLICK • In inspiration → ↑ RV preload → ↑ RV end-diastolic pressures → pulmonary valve may partially open up just BEFORE systole → ↓ overall excursion of the pulmonary valve → reduced intensity of ejection sound • PAH – RV end-diastolic pressures still remain considerably lower than pulmonary artery diastolic pressures, hence the ejection click variation with respiration is absent Different pathologies → different variations Pulmonary valve stenosis and idiopathic dilatation of pulmonary arteries → ejection click varies with respiration PAH – ejection click does not vary with respiration RESPIRATORY VARIATION 23-11-2018

RESPIRATORY VARIATION EXPIRATION Normal expiration → ↓ lung volume → ↑ pulmonary venous flow Therefore, left sided murmurs are loudest during expiration and diminish or remain unchanged during inspiration THE SECOND HEART SOUND DURING RESPIRATION Widening of normal splitting of second heart sound (wide variable splitting) Delayed electrical activation – RBBB Prolonged mechanical systole – Pul. Stenosis Prolonged hangout interval – Idiopathic dilatation of Pulmonary Artery RESPIRATORY VARIATION 23-11-2018

THE SECOND HEART SOUND DURING RESPIRATION Wide fixed splitting (ASD) Pulmonary impedance is almost minimum to incorporate the ↑ pulmonary blood flow → inspiration therefore does not cause a further fall in impedance and hence does not cause a further separation of A2 and P2 → thereby appearing fixed Paradoxical splitting of S2 Inherently delayed A2 component due to Delayed electrical activation – LBBB Delayed mechanical systole – Aortic Stenosis RESPIRATORY VARIATION 23-11-2018

RESPIRATORY VARIATION VALSALVA MANOEUVRE Forced exhalation against a closed glottis As if to have a bowel movement Examiner places a hand on the patient’s abdomen to make sure the abdominal muscles are tightened Alternative method – blow into a mercury manometer to maintain a pressure of ≥ 40 mmHg Usually continued for around 10 secs If done for > 10 secs, chance of syncope Make sure patient isn’t blowing using his cheeks → false negatives RESPIRATORY VARIATION 23-11-2018

RESPIRATORY VARIATION PHASES Phase I Strain phase – blood squeezed from the lung into the left heart → transient ↑ in SBP Subsequent ↓ in right sided cardiac output → ↓ left sided cardiac output → ↓ SBP Sympathetic stimulation with vasoconstriction and tachycardia Phase II Release of strain → ↑ right sided blood flow → followed gradually by ↑ left sided blood flow Right sided murmurs ↑ in 1-4 cardiac cycles, left sided ↑ by 5-10 cardiac cycles Overshoot of SBP due to previous sympathetic stimulation and vasoconstriction → reflex bradycardia RESPIRATORY VARIATION 23-11-2018

RESPIRATORY VARIATION ABNORMAL PHASES If absent overshoot → suspect Mild LV dysfunction Autonomic failure If absent ↓ in SBP during strain phase Overt CCF Large L → R shunt Transient ↓ in coronary blood – contraindicated in k/c/o myocardial ischemia or recent infarction RESPIRATORY VARIATION 23-11-2018

RESPIRATORY VARIATION EFFECTS All murmurs, both left and right sided → ↓ in intensity : except Mitral Valve Prolapse (MVP) ↓ LV volume → earlier leaflet prolapse → ↑ intensity and duration of murmur Manoeuvre is unreliable → not to be completely relied upon → variable responses obtained Hypertrophic obstructive cardiomyopathy (HOCM) Dynamic obstruction → ↑ with a ↓ in LV volume Highly specific but not very sensitive sign RESPIRATORY VARIATION 23-11-2018

MITRAL STENOSIS – AN EXCEPTION FOR VALSALVA MANOEUVRE Valsalva causes an overall ↓ in left sided cardiac output → works towards ↓ing the intensity of MS murmur Ensuing tachycardia → incomplete emptying of the LA → backlogging and elevated LA pressures → ↑ in LA-LV gradient → works towards ↑ing the intensity of MS murmur Above to mechanisms cancel each other out → hence, no change in MS murmur RESPIRATORY VARIATION 23-11-2018

VALSALVA FOR DIFFERENTIATING A2 AND P2 During strain phase → both A2 and P2 are diminished in intensity During release phase →P2 first returns to baseline intensity, followed later by A2 RESPIRATORY VARIATION If fixed paradoxical split is present, can be found out by this method. 23-11-2018

SUSTAINED HANDGRIP 23-11-2018

METHOD Squeeze examiner’s fingers with one or both hands Calibrated dynamometer Duration Minimum of 60-90 secs must elapse before a significant change in BP and heart rate is observed Avoid concomitant Valsalva manoeuvre SUSTAINED HANDGRIP Parameter Handgrip Dynamic exercise Heart rate ↑ ↑ ↑ ↑ Cardiac output SBP 23-11-2018

EFFECTS Systemic vascular resistance Changes only if strain applied is > 50% of patient’s maximum. EFFECTS ↑ LV filling pressures Augmented LV S3 and S4 Systemic vascular resistance Changes only if strain applied is > 50% of patient’s maximum. Further, ↑ LV filling pressures AND Augmented LV S3 and S4 seen in patients with LV dysfunction apart from ↑ in heartrate, CO and SBP. Murmurs that are augmented AR MR MVP (MR) VSD SUSTAINED HANDGRIP 23-11-2018

EFFECTS Murmurs that are reduced in intensity or show no change AS HOCM → variable response → hence not a very useful manoeuvre in this condition Reason for variable response in HOCM ↑ SVR tends to ↓ the gradient Tachycardia tends to ↑ the gradient SUSTAINED HANDGRIP CANCEL EACH OTHER OUT 23-11-2018

EFFECTS IN rheumatic mitral stenosis Tachycardia → incomplete LA emptying → ↑ LA filling pressures → ↑ LA-LV gradient → augmentation of murmur Helps distinguish between OS and S3/pericardial knock OS moves closer to A2 S3/pericardial knock does not change position SUSTAINED HANDGRIP 23-11-2018

POSTURAL CHANGES 23-11-2018

PHYSIOLOGY Supine to standing → changes similar to Valsalva manoeuvre Standing ≈ Valsalva Squatting ≈ opposite of Valsalva The quicker the change in posture, the more dramatic the change in murmur Squatting Compression of femoral arteries → ↑ mean aortic pressure → ↑ afterload Compression of leg veins and abdomen → ↑ venous return → ↑ preload For those unable to perform squatting → passive flexion of both legs towards abdomen in supine position mimics squatting mediated hemodynamic changes. POSTURAL CHANGES 23-11-2018

EFFECTS Standing – all cardiac murmurs ↓ in intensity Except HOCM and MVP Changes similar to Valsalva → ↑ on standing Postural change from supine to standing → venous pooling → ↓ stroke volume → reflex tachycardia and ↑ in SVR Respiration Valsalva Handgrip Postural change POSTURAL CHANGES Require an intact and functioning autonomic nervous system to manifest effects on murmurs. ∴ in chronic CCF, these manoeuvres are not useful. So are the physical changes in these maneuvers. 23-11-2018

POST-VPC / LONG DIASTOLE IN AF No active patient cooperation required Intactness of ANS not required 23-11-2018

POST-VPC / LONG DIASTOLE IN AF PHYSIOLOGY Effects observed 1. ↑ preload → frank-starlings law → ↑ contractility 2. ↓ aortic diastolic pressure POST-VPC / LONG DIASTOLE IN AF 23-11-2018

POST-VPC / LONG DIASTOLE IN AF EFFECTS Aortic stenosis (valvular, supravalvular and discrete subvalvular) ↑ forward flow ↑ gradient between LV and aorta ↑ intensity of the murmur HOCM Variable effects due to opposing influences of (↑ preload) and (↑ contractility with ↓ aortic impedance) Also, associated MR murmur may interfere with intensity estimation POST-VPC / LONG DIASTOLE IN AF 23-11-2018

POST-VPC / LONG DIASTOLE IN AF EFFECTS Mitral regurgitation No change in intensity ↑ preload and contractility is compensated by ↓ afterload, thereby preferentially pushing the extra volume of blood into the aorta rather than the LA There still is an ↑ regurgitant flow into the LA in the isovolumetric contraction phase of LV However, the regurgitant flow in the later part of systole to LA is ↓ Why TR murmur does not follow the same principles of MR? ↓ afterload after a VPC is a feature specific for the systemic circulation Further, the pulmonary circulation is already a very low impedance circulation, hence any further drop in the RV afterload would be clinically subtle, it at all present. POST-VPC / LONG DIASTOLE IN AF 23-11-2018

PHARMACOLOGICAL MANEUVERS AMYL NITRITE INHALATION 23-11-2018

AMYL NITRITE INHALATION PHYSIOLOGY Method Hold ampoule in a tissue wrap near the patient’s nose and mouth Break ampoule and ask patient to take 3 deep breaths Actions Onset – within 15 secs Duration – 30 secs BP returns to normal in 1-2 minutes Reflex tachycardia occurs by 30-60 secs after inhalation AMYL NITRITE INHALATION 23-11-2018

AMYL NITRITE INHALATION EFFECTS ↓ afterload Initial ↓ in preload Reflex tachycardia → ↑ in stroke volume AMYL NITRITE INHALATION Initially, no increase in stroke volume 23-11-2018

AMYL NITRITE INHALATION EFFECTS All LVOT systolic murmurs ↑ in intensity Aortic stenosis Valvular Supravalvular Discrete subvalvular HOCM Aortic regurgitation murmurs → softens MR murmur Decreases in intensity CONTRAST WITH POST VPC STATE AMYL NITRITE INHALATION •In post-VPC state, there is ↑ in preload and ↓ in afterload. If the afterload had remained the same, the absolute regurgitant volume (which translates as the flow) through mitral valve would have ↑. But since there is also a ↓ in afterload, the amount of extra volume that needed to be regurgitated to LA gets diverted to the aorta. The effect of ↑ in preload gets cancelled out by the effect of ↓ in afterload and hence the intensity of the MR murmur does not change. •In amyl nitrite inhalation, there is primarily a ↓ in afterload with a ↓ in preload. Supposing the afterload had remained the same, the ↓ in preload itself would have reduced the regurgitant volume and hence the intensity of murmur. But here, the ↓ in afterload further decreases the regurgitant volume and hence the intensity of murmur. 23-11-2018

CONGENITAL HEART DISEASE VSD PDA TOF Differentiating PS with intact ventricular septum vs. TOF with PS PS murmur increases while the latter decreases Differentiating between valvular MS vs. Austin Flint murmur MDM of valvular MS increases while the latter decreases AMYL NITRITE INHALATION Murmur intensity decreases because the ↓ systemic vascular resistance ↑ the flow through the systemic circulation and ↓ the flow through the shunt ↓ in pulmonary flow murmur due to ↑ in R→L shunt 23-11-2018

THANK YOU 23-11-2018