31.7.2014 Flashcards
Anginal symptoms result when fixed occlusion is more than
70%
Coronary artery disease
More than 50% occlusion of epicardial coronary arteries
Role of hormone replacement in CAD prevention
No role
Typical angina
- sub sternal chest discomfort or heaviness with characteristic quality and duration
- precipitated by stress
- relieved by rest or nitroglycerine
Atypical chest pain meets only two of the criteria
Non cardiac chest pain meets one or none of the criteria
Grading system for angina
Canadian cardiovascular society classification
Associated symptoms of angina
Dyspnea Diaphoresis Nausea Vomiting Dizziness
Minimal or atypical symptoms of angina are seen in
Women
Diabetes
CKD
Angina equivalents
Dyspnea
Nausea
Epigastric pain
Cardiovascular causes of chest pain
Aortic stenosis Syphilitic AR- nocturnal angina due to coronary osteal stenosis HOCM Prinzmetal angina Syndrome X Pericarditis Aortic dissection Cocaine use
Non-cardiac chest pain responsive to nitrates
Esophageal spasm
Tsetse syndrome
Costochondritis
Non cardiac causes of chest pain
Anemia Thyrotoxicosis Biliary colic Pneumonia Costochondritis Esophageal disease
Indications for cardiovascular stress testing
Without known CAD
Stress testing as screening in asymptomatic patients is not recommended
Pts with anginal symptoms
Asymptomatic intermediate risk patients with high risk occupations or planning intensive exercise regimen
Asymptomatic high risk patients with risk factors like diabetes or peripheral vascular disease
With known CAD
Post MI risk stratification
Preoperative risk assessment
Recurrent angina after medical therapy or revascularisation
Test of choice for assessing intermediate risk for CAD pts
Exercise stress testing
Protocol used in exercise stress testing
Bruce protocol
Bruce protocol
3 min stages of increasing treadmill speed and incline
HR,BP and ECG are monitored
Target Heart rate to be reached in exercise stress testing
85% of maximum predicted for age
Exercise stress testing is considered positive if
New ST segment depressions of more than 1mm in multiple leads
Hypotensive response to exercise
Sustained ventricular arrythmias precipitated by exercise
Duke treadmill score
Minutes exercised- 5maximum ST deviation- 4anginal score
Management based on duke treadmill score
More than 5 - medical therapy
-10 to 4 : further testing based on risk factors
Less than -10 : coronary angiography
Indications for stress testing with imaging
Pre excitation LVH LBBB or paced rhythm Intra ventricular conduction delay Digoxin effects Resting ST-T wave changes
Substances used in myocardial perfusion imaging
Thallium 201
Technitium 99m
Substance used in magnetic resonance perfusion imaging
Adenosine
Contraindications to stress testing
Acute MI in past 2 days
UA not previously stabilised by medical therapy
Cardiac arrythmias causing symptoms or hemodynamic compromise
Symptomatic severe aortic stenosis
Symptomatic heart failure
Acute pulmonary embolus,myocarditis,pericarditis,aortic dissection
Gold standard test for evaluating coronary anatomy
Coronary angiography
Limitations of coronary CT angiography
Radiation exposure
Requirement of HR less than 70 bpm
Presence of coronary calcification or stents
Role of dual therapy,Aspirin+clopidogrel
Pts with prior MI
Dosage of beta blockers is adjusted according to
Until a heart rate of 50-60 is reached
CCB contraindicated in angina
Short acting dihydropyridines(nifedipine)
Contraindications to beta blocker therapy
Active bronchospasm
Significant AV block
Marked resting bradycardia
Poorly compensated HF
When should an angina patient on nitrate therapy seek prompt medical help
Rest pain
Pain not relieved by third dose of nitrates
Drugs used in treatment of chronic stable angina
Aspirin and clopidogrel Beta blockers CCB nitrates Ranolazine ACE inhibitors Intensive statin therapy
Failure of medical therapy in angina
Atleast two or preferably 3 anti anginal drugs have been used
Indications of coronary revascularisation procedures in angina patients
Angina refractory to medical therapy
Angina and reduced LV function
Severe activity limiting angina(class 3 and 4)
Angina in the presence of left main or triple vessel disease
CABG in angina is preferred in
Diabetics with multivessel disease and LV dysfunction
Trial that compared PCA versus CABG in untreated left main stem or triple vessel disease
Syntax(CABG is superior)
Steele rule of thirds
- canal of atlas is about 3 cm in its AP diameter
- spinal cord, odontoid process, and free space for cord are each about 1 cm in diameter
- anterior displacement of the atlas that exceeds one centimeter may jeopardize the adjacent segment of the spinal cord
Erbs spastic paraplegia is seen in
Syphilis
Graft patency in CABG
90% for 10 years if internal mammary artery is used
40-50% for Saphenous vein grafts
Novel therapies for treatment of chronic stable angina
Transmyocardial LASER revascularisation
Therapeutic angiogenesis with VEGF or FGF
Non selective beta blockers
Propranolol
Nadolol
Timolol
Pindolol
Onset and duration of action of sublingual nitroglycerin
Onset: 2-5 min
Duration: 10-30 min
Onset and duration of action of oral isosorbide dinitrate
Onset: 30-60 min
Duration: 4-6 hr
Peripheral opioid receptor antagonists
Alvimopen
Methylnaltrexone
Use of peripheral opioid antagonists
Postoperative illeus and constipation caused by opioids
ECG criteria for STEMI
ST elevation of more than 0.1mV in two or more contiguous leads
New LBBB
Diff btw STEMI and UA
Cardiac bio markers are elevated in NSTEMI
ECG findings in NSTEMI
ST segment depression
T wave inversions
Transient ST elevation(rarely)
Most common ACS
UA
Which is common STEMI or NSTEMI?
NSTEMI 2/3
STEMI 1/3
NSTEMI due to increased myocardial oxygen demand
Severe Anemia
Hypertensive crisis
Atherosclerotic plaques that are prone to rupture are called
Vulnerable plaques(difficult to detect angiographically as they don’t cause mechanical obstruction)
