It involves detelnlining the effects on heart sounds and murmurs of va-ious physiological and pharmacological manoeuvres, which alter the circulatory dynamics.
The manoeuvres commonly employed are:
1) Respiration
2) Valsalva manoeuvre
3) Postural changes.
Pren~ature ventricular contractions.
Iso~~letric exercise.
Phar~nacologic agents, e.g., amyl nitrite.
1)Respiration
a) S,: Splitting of S, is audible during inspil-ation.
b) Diastolic Sourrds arrd Ejectiorz Sourrds: Inspiration augments RVS, and RVS, \vhereas LVS, and LVS, are diminislled. The only right-sided event to diminish during inspiration is the pulmonary ejection click in patients with pulmonary stenosis. Respiration doesn't affect the intensity of aortic ejection sounds, except in Tetralogy of Fallot with pulmonary atresia.
c) Murrnurs: Murmurs originating from right side of the heart are accentuated during inspiration. In patients with MVP, the n~idsystolic click and the systolic murmur occur earlier in systole and may get accentuated during inspiration as reduction in the LV cavity iimcreases the redundancy of the mitral valve and hence increases the prolapse.
2) Valsalva Rlanocuvre
This consists of deep inspiration followed by forced inhalation against a closed glottis for 10-20 seconds. It can be performed by placing examiners hand over patients abdoinen and asking llinl to apply as much force as possible.The normal response consists of four phases:
Phase I: Transient rise in systemic BP as straining commence.
Phase 11: Reduced venous return and systolic BP with reflex tachycardia.
Phase 111: Abrupt, transient reduction in syslenlic BP as straining ceases.
Phase IV: Overshoot of systelnic BP and reflex bradycardia.
Phase V: A,-P, interval narrows.
S, and S, arc attenuated.
Murmurs of AS and PS and of MR and TR diminish (as stroke volume and systemic BP falls).MVP click and systolic murnlur begins early (as LV volunle is reduced).
The manoeuvres commonly employed are:
1) Respiration
2) Valsalva manoeuvre
3) Postural changes.
Pren~ature ventricular contractions.
Iso~~letric exercise.
Phar~nacologic agents, e.g., amyl nitrite.
1)Respiration
a) S,: Splitting of S, is audible during inspil-ation.
b) Diastolic Sourrds arrd Ejectiorz Sourrds: Inspiration augments RVS, and RVS, \vhereas LVS, and LVS, are diminislled. The only right-sided event to diminish during inspiration is the pulmonary ejection click in patients with pulmonary stenosis. Respiration doesn't affect the intensity of aortic ejection sounds, except in Tetralogy of Fallot with pulmonary atresia.
c) Murrnurs: Murmurs originating from right side of the heart are accentuated during inspiration. In patients with MVP, the n~idsystolic click and the systolic murmur occur earlier in systole and may get accentuated during inspiration as reduction in the LV cavity iimcreases the redundancy of the mitral valve and hence increases the prolapse.
2) Valsalva Rlanocuvre
This consists of deep inspiration followed by forced inhalation against a closed glottis for 10-20 seconds. It can be performed by placing examiners hand over patients abdoinen and asking llinl to apply as much force as possible.The normal response consists of four phases:
Phase I: Transient rise in systemic BP as straining commence.
Phase 11: Reduced venous return and systolic BP with reflex tachycardia.
Phase 111: Abrupt, transient reduction in syslenlic BP as straining ceases.
Phase IV: Overshoot of systelnic BP and reflex bradycardia.
Phase V: A,-P, interval narrows.
S, and S, arc attenuated.
Murmurs of AS and PS and of MR and TR diminish (as stroke volume and systemic BP falls).MVP click and systolic murnlur begins early (as LV volunle is reduced).
HOCM illurmur conles early in systole.
Phase VI: S, split widens.
Murmurs on right side are accentuated. (As venous return increases).This manoeuver shouldn't be performed in patients with IHD because of the acconlpanying fall in coronary blood flow.
3)Muller Manoeuver
In this manoeuver, patient forcibly inspires while the nose is held closed and mouth firmly sealed for 10 seconds.It exaggerates the inspiratory efforts and hence augments the right side murmurs and filling sounds.
4)Postural Cliarlgcs
a) On sudden assumption of supine position from standing 011 sittiiigpositioli or suddcn passive eleva~ion of both Icgs: Venous rcturn irlcrcascs that increases tlie RV stroke volu~iic for several cardiac cycles imniediately and later on the LV stroke volume increases and consequently S, split widens. RS, and RS,, systolic niurnlurs of PS, TR and VSD arc aug~i~ented inlmcdiately. Later on LVS, LVS,- niurniur of AS, MR and VSD are accentuated; due to increased LV ehd diastolic volulne the click dnd systolic lnurniur of MVP and HOCM are diminished.
b) Rapid standing or sitting up from supine position lias opposite effect.
c) With assunlption of left lateral dccubitus tliere is accentuation S,, LVS, and LVS,, OS, murnlur associatcd with MS and MR, ~uidsystolic click and late systolic murmur of MVP.
5)Isonietric Excrcisc
Can be carried out by doing handgrip excrcise wllicll is sustaiiied over 20-30 second. It results in transiellt increase in SVR, BP, Heart rate, Cardiac output and LV filling pressure.LVS, and LVS, are accentuated.
Systolic nu-nlur of AS is diminislled with reduction in gradient across the valve.Murmur gf AR, MR and VSD is accentuated. Systolic niumiur of HOCM diminished and systolic ciick and niuiniur of MVP are delayed (as LV volu~iie increases).
This should be avoided in patient with niyocardial ischaeniia and ventricular arrhythmia.
6)Pharmacologic Agents
a) A111yl Nitrite
It produces vasodilatation whicli initially results in niarked fall in BP and in the next 30-60 seconds there is reflex tachycardia followed by an increase in cardiac output.
An ampoule of amyl nitrite is taken in gauze and crushed near the supine patients nose and the patient is asked to inhale over 10-15 seconds.Major auscultatory changes occur in the 1st 30 secorzds aJer iitlzalatioil:S, is augmented, A, is diminished, and pathological S , is augmentcd.A,-OS interval shortens.Murn~urs of MR, VSD and AR are reduced.Systolic mcrmurs AS, PS, HOCM and TR are accentuated.Diastolic murnlurs of MS, TS and PR are accentuated.PDA nlurnlur and of AV fistula are reduced.
If amyl nitrite is not available, the test can be done using isosorbide dinitratc.b) Phenylephine and Meihoxamine They have opposing effects to amyl nitrite as they increase the systemic BP.phenylephine due to its shorter duration of action is preferred.Both cause reflex bradycardia and reduced contractility and cardiac output. Both are given intravenously, with elevation of BP lasting for 3-5 minutes with methoxainine.These agents should not be used in patients with systemic hypertension or those in CHF.
Pericardial Rub
Generation of sound: The sound is generated due to rubbing of visceral and parietal pericardial surfaces against each other. In case rub is suspected but not heard in supine position, the following technique can be used. Apply the stethoscope firmly to precordium while thc patient rests on elbows and knees (as the opposition of two layers of pericardiuln is better).Characteristic: Superficial, scratchy, leathery sound component. In sinus rhythms,the typical rub is three phased (one systolic and two diastolic).
Phase VI: S, split widens.
Murmurs on right side are accentuated. (As venous return increases).This manoeuver shouldn't be performed in patients with IHD because of the acconlpanying fall in coronary blood flow.
3)Muller Manoeuver
In this manoeuver, patient forcibly inspires while the nose is held closed and mouth firmly sealed for 10 seconds.It exaggerates the inspiratory efforts and hence augments the right side murmurs and filling sounds.
4)Postural Cliarlgcs
a) On sudden assumption of supine position from standing 011 sittiiigpositioli or suddcn passive eleva~ion of both Icgs: Venous rcturn irlcrcascs that increases tlie RV stroke volu~iic for several cardiac cycles imniediately and later on the LV stroke volume increases and consequently S, split widens. RS, and RS,, systolic niurnlurs of PS, TR and VSD arc aug~i~ented inlmcdiately. Later on LVS, LVS,- niurniur of AS, MR and VSD are accentuated; due to increased LV ehd diastolic volulne the click dnd systolic lnurniur of MVP and HOCM are diminished.
b) Rapid standing or sitting up from supine position lias opposite effect.
c) With assunlption of left lateral dccubitus tliere is accentuation S,, LVS, and LVS,, OS, murnlur associatcd with MS and MR, ~uidsystolic click and late systolic murmur of MVP.
5)Isonietric Excrcisc
Can be carried out by doing handgrip excrcise wllicll is sustaiiied over 20-30 second. It results in transiellt increase in SVR, BP, Heart rate, Cardiac output and LV filling pressure.LVS, and LVS, are accentuated.
Systolic nu-nlur of AS is diminislled with reduction in gradient across the valve.Murmur gf AR, MR and VSD is accentuated. Systolic niumiur of HOCM diminished and systolic ciick and niuiniur of MVP are delayed (as LV volu~iie increases).
This should be avoided in patient with niyocardial ischaeniia and ventricular arrhythmia.
6)Pharmacologic Agents
a) A111yl Nitrite
It produces vasodilatation whicli initially results in niarked fall in BP and in the next 30-60 seconds there is reflex tachycardia followed by an increase in cardiac output.
An ampoule of amyl nitrite is taken in gauze and crushed near the supine patients nose and the patient is asked to inhale over 10-15 seconds.Major auscultatory changes occur in the 1st 30 secorzds aJer iitlzalatioil:S, is augmented, A, is diminished, and pathological S , is augmentcd.A,-OS interval shortens.Murn~urs of MR, VSD and AR are reduced.Systolic mcrmurs AS, PS, HOCM and TR are accentuated.Diastolic murnlurs of MS, TS and PR are accentuated.PDA nlurnlur and of AV fistula are reduced.
If amyl nitrite is not available, the test can be done using isosorbide dinitratc.b) Phenylephine and Meihoxamine They have opposing effects to amyl nitrite as they increase the systemic BP.phenylephine due to its shorter duration of action is preferred.Both cause reflex bradycardia and reduced contractility and cardiac output. Both are given intravenously, with elevation of BP lasting for 3-5 minutes with methoxainine.These agents should not be used in patients with systemic hypertension or those in CHF.
Pericardial Rub
Generation of sound: The sound is generated due to rubbing of visceral and parietal pericardial surfaces against each other. In case rub is suspected but not heard in supine position, the following technique can be used. Apply the stethoscope firmly to precordium while thc patient rests on elbows and knees (as the opposition of two layers of pericardiuln is better).Characteristic: Superficial, scratchy, leathery sound component. In sinus rhythms,the typical rub is three phased (one systolic and two diastolic).
- Mid systolic
- Diastolic
- Pre systolic
The rnid systolic phase is most consistent followed by the presystolic phase(disappears in atrial fibrillation).
Most likely causes o F pericardial friction rules are Rheumatic, Pericarditis,tuberculosis, Pericarditis.Immediately post open heart surgery
MI
Uremia.
It can often be heard posteriorly over the back.
Most likely causes o F pericardial friction rules are Rheumatic, Pericarditis,tuberculosis, Pericarditis.Immediately post open heart surgery
MI
Uremia.
It can often be heard posteriorly over the back.
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.