Transcript Cardiomyopaties

CARDİOMYOPATHİES
Definition:
Cardiac dysfunction caused by myocardial disease.
Five Categories:
1- Dilated Cardiomyopathy ( genetic +).
2- Hypertrophic Cardiomyopathy ( genetic +).
3- Restrictive Cardiomyopathy.
4- Arrythmic Cardiomyopathy (genetic +).
5- Unclassified Cardiomyopathy .Disease has not fature
1- 4 (Fibroelastosis and Mitochondrial disease)
- Some of the Infiltrative and systemic diseases cause
Spesific heart muscle disease called: “Secondary
Cardiomyopathy” or “Specific Cardiomyopathy”.
Secondary Myocardial Diseases
Definition:
Myocardial disease of known origin. (Secondary
Cardiomyopaty)
7 Subgroups:
1- Ischemic Cardiomyopathy
2- Hypertensive Cardiomyopathy
3- Valvular Cardiomyopathy
4- Alcoholic Cardiomyopathy
5- Metabolic Cardiomyopathy
6- Muscular Distrophy Cardiomyopathy
7- Peripartum Cardiomyopathy
HYPERTROPHİC CARDİOMYOPATHY (HCM)
Definition: Massive ventricular hypertrophy with no
absolute cause.
Not all of these patients show IHSS (Idiopatic
Hypertrophic Subaortic Stenosis) or HOCMP
(Hypertrophic Obstructive Cardiomyopathy) features.
There is no pressure gradient at left ventricle
outflow(LVOT) tract in 1/3 of patient. (Rest or provocated
gradient).
HCMP prevalance: 1/500. HCMP is the most prevalant
genetic cardiovascular disease.
Nearly %60 inherited. Relation with mutation of betamyosin heavy chain and also other sarcomeric proteins
has been shown. (Troponin- T, -I, -C, Myosin Related
Protein- C etc.).
HCM ıs the most frequent cause of sudden cardiac
death among young people including athletes.
Structure of Human Sarcomere: Contraction is carried
out by the interaction of actin and myosin.
The process begins with the ligation of calcium to troponin
complex (I, C, T) and alpha-tropomyosin. Then, actin binds to
myosin and activates ATPase of the spheric myosin, so that
contractile function is carried out. Cardiac myosin binded
protein C binds to myosin and starts contraction.
HYPERTROPHIC CARDIOMYOPATHY: Cellular changes
of myocytes. Cell disarrangement ise seen on
microscope. Left: Organized and parallel cell
arrangement in normal myocardium. Right:
Disarrangement affects impuls conduction and
promotes ventricular arrythmias.
Common HCM types: (A)- LV free wall, diffusely hypertrophied İVS.
(B)- Asymmetric septal hypertrophy (C)- MassiveConcentric LV
hpertrophy ( involve walls, papillary muscles).
(A)-
(B)-
-(C)
HCMP: Patophysiology
Most patients have septum hypertrophy with non-dilated LV and/or
RV cavity.
Hypertrophy of the septum may be diffuse or only the upper, mid or
apical hypertrophy of the septum may take place.
Hypertrophy is extednded to the LV free wall in most of the patients.
Diastolic filling is impaired because of the incomplete relaxation and
compliance of the LV.
Hypertrophic LV empties most of its content in the first half of
systole. (Hyperdynamic systolic function”).
Mitral anterior leaflet is displaced towards septum during mid
systole and this causes obstruction the the LV outflow tract during
this period.
At the obstructive phase of the disease mitral regurgitation is
always present.
There ise resting pressure gradient at LV outflow tract in %35 of
patients.
Gradient can be precipitted at the other %25 (by augmenting
myocardial contraction, and reducing ventricular volume).
Fibrosis and occlusive disease in in small coronary arteries.
The major coronary arteries, are wide and patent unless occlusive
atherosclerosis occurs.
HCM:
Symtomps: Angina, Dyspne, Presyncope, Syncope.
Physical Findings:
1- Before LV beat, LA beat is palpated (S4): Is present even in the
absence of any gradient or murmur. Impaired LV relaxation.
2- LVOT Sistolik ejectıon Murmur: Crescendo-Decrescendo,
starts with S1 and ends with S2.
Best heard between apex and left sternal border. Cervical radiation is
weak. Augmented by manouvers and drugs which decrease
preload. (Valsalva, standing, amyl nitrite). Attenuates with
increasing afterload (squating, handgrip fenilefrin).
3- MR murmur: Heard at late systole, radiates to axilla, and
related with LV outflow obstruction. Mitral diastolic rumble and
Paradoxic splitting of S2 may be heard.
4- Hyperdynamic carotis pulse.
HCM: Clinical Presentation and Mechanisms
Chest pain: Ischemia, LVOT ob. Reduced coronary
perfusion pressure.
Exertional dyspnea: Diastolic dysfunction.
Reduced functional capacity: LVOTob, systolic
dysfunction, AFwith uncontrolled rapid ventricular
rate.
Palpitation: SVT, AF, frequent VPB, non-sustained VT.
Syncope/Presyncope: Supraventricular arrythmia,
LVOTob, vasovagal, high VT rate .
İnadequate increase cardiac output during the effort.
Cardiac arrest: VT, SVT, AF, VF, bradyarrythmia.
HCM: Sudden death:
Supraventricular arrythmia is present in %20-50 of the
patients, but sudden death is caused by ventricular
arrythmia.
Major Risk Factors of Sudden Death:
1- Patient who survive after cardiac arrest (sustained
ventricular tachycardia).
2- Arrythmia and abnormal blood pressure response to
excersize.
3- Non-sustained ventricular tachycardia (Holter).
4- Family history of sudden cardiac death and syncope in
more than two first degree relatives before 40 years.
5- LV Wall thickness >30 mm.
HCM: Other manifestations.
Atrial Fibrillation
Seen in %15 of patients with HCM.
Absence of atrial systole. Rapid ventricular rate
causes pulmonary edema or hypotension.
Rapid ventricular rate causes detoriation of
functional capacity.
By conversion to sinus rythm or decreasing heart
rate functional capacity improves.
Endocarditis:
May occur on aortic or mitral valves. Unexpected heart
failure and IE symptoms or signs should be
suggest İE in HCM patiernts.
HCM: ECG and CHEST FİLM
Chest film: May be normal-large left heart chambers. . No
aortic calcification.
ECG: Is anormal in %97 of symptomatic HCMP, and in %90
of asymptomatic HCMP patients.
AF is detected in %15.
Non-sustained VT is frequent. .
Q waves in DII, DIII, aVF and D1, aVL, V5, V6 (and less
frequently in V1-3). This sign shows hypertrophy, and
causes pseudoinfarct patern.
Intraventricular conduction delay.
High voltage findings of LVH.
T waves of LVH.
Huge negative T waves are frequently seen in apical HCMP
high precordial QRS voltage.
Short PR and pre-exitation may be seen, but is
infrequent.
HCMP: Echocardiographic Hallmarks
Asymetric (dispropotionate) septal thickening: Septum
to posterior wall ratio > 1.5
LV myocardial segment >1.5 cm in thicknesss.
Poor Septal contractıon. Hypercontractile free posterior
wall.
Systolic anterior motıon of the mitral valve (SAM) when
outflow tract gradient >30 mmHg .
Mid-systolic closure of aortic valve.
Small LV cavity.
Mitral regurgitation is frequent.
LVOT gradient at rest present in about %35 of patients
HCM: Characteristic ECG paterns.
Left axis deviation
LBBB
Pathologic Q wave on anterolateral leads.
T wave inversion (commonly in İnferolateral leads)
ST segment changes.
Criteria for left atrial enlargement.
V3-5 or V4-6 huge T wave inversion (“Distal- apikal
HCM”
HCM: Pseudoinfarction patern, Q wave.
HCMP: Management. Pharmacologic and
surgical intervention.
OBSTRUCTIVE
PHASE:
Beta bockers: (Especially
latent obstruction).
Verapamil.
Disopiramid. Amiodaron:
(SVT, VA + ).
Digoxin: (contraindicated).
Diüretic: (contraindicated).
ACEI (contraindicated).
Surgery: Septal myectomy.
Septal ablation.
ICD is indicated in severe
VA.
LAST PHASE:
Beta blockers: (small
doses)
Verapamil:Contraindicate.
Disopiramid:Contraindicate.
Digoxin: Beneficial.
Diuretic: Beneficial.
ACEI: Beneficial in patients
with LV dilatation and HF.
Surgery: Transplantation.
HOCM: LVOT gradient.
Hypertrophic obstructive cardiomyopathy (HOCM): As
Mitral valve changes:When the LVOTis narrowed, blood rushes
through the passageway toward the aortic valve(like tight garden
hose nozzle), dragging the leaflets of the mitral valve with it. Mitral
valve normally functıons keep blood floıwing in direction from the
left atrium (upper heart chamber) to the LV. However increased
force of blood caused by HCM pulls the valve open and may cause
blood leak backward (called regurgitatıon )into the LA.
NORMAL
LVOTobs.
Anterıor replacement of the papillary muscle in HOCM :
MR, SAM
HOCM: Septal myectomy: Before the operatıon There is severe
hypertrophy of the basal septum, whith systolic anterior motıon of the mitral
valve (-A-). This results in severe LVOT obs. as well as MR. During the
surgery (-B ), yhe portıon of the basal septum that project into the outflow
tract is removed by scalpel, resulting in abolitıon of the LVOTobs. (-C-). There
is no longer SAM, and theMR abolished.
HOCM: Septal ablation (with absolute ethanol).
İndication: LVOT gradient at rest > 30-50 mmHg. With
provocation 75-100 mmHg.
HOCM: Decreased LVOT gradient after septal ablation.