CVD II - HF and Valv HD Flashcards
what are the functions of the SA node
- primary pacemaker
- regulates atrial function
- produces P wave - atrial depolarization
what is the function of the AV node
- regulates atrial impulses entering ventricles
- slows conduction rate of SA generated impulses
what is happening during the QRS complex
simulataneous depolarization of the ventricles
what happens during the T wave
repolarization of the ventricles
disruption of the electrical impulse generation or conduction in the heart leads to what abnormal cardiac functions
- formation of abnormal impulse
- increased impulse formation
- enhanced or abnormal impulse formation
- delayed depolarization
- re-excitation of the heart after refractory period
disruption of the electrical impulse generation or conduction in the head may be due to an area of:
- infarction
- ischemia
- electrolyte imbalance
- medication
the most common cause of sudden cardiac death is:
ventricular fibrillation
what are the causes of arrhythmias
- cardiovascular disorders
- pulmonary disorder
- autonomic disorder
- hyperthyroidism
- drugs
- electrolyte imbalance
- anxiety and anger
what cardiovascular disorders cause arrhythmias
- MI
- mitral stenosis
- valvular disease
- ischemic heart disease
- congestive heart failure
what pulmonary disorders cause arrhythmias
-pneumonia
- obstructive lung disease
what drugs cause arrhythmias
- epinephrine
- alcohol
- digitalis
- morphine
- beta blockers
- tricyclic antidepressants
what are the supraventricular arrhythmias
- sinus nodal disturbances: sinus arrhythmias, sinus tachycardia, sinus bradycardia
- disturbances of atrial rhythm: premature atrial complexes, atrial flutter
- ventricular tachycardia
- ventricular fibrillation
what qualifies bradycardia
less than 60 beats/min
what qualifies tachycardia
greater than 100 bpm
what are the symptoms of arrhythmias
- palpitations, fatigue
- dizziness, syncope, angina
- CHF
- SOB
- orthopnea
- peripheral edema
describe atrial fibrillation
- most common arrhythmia
- rapid uncontrolled atrial activity
- irregularly irregular rhythm
- risk of arterial clot formation: embolism and stroke
what is a heart block
- impulse is partially or completely blocked
- prolonged or no conduction
what are the degrees of heart block and describe each
- first degree: longer conduction time
- second degree: Mobitz I: more prolonged and no P wave. Mobitz II: repetitive or occasional sudden blocks without previous prolonged conduction time
- third degree: no impulses- complete block. indication for pacemaker
describe ventricular arrhythmias
- premature ventricular complexes (PVCs)
- common
- abnormal QRS complex + pause
- increased risk of death if patients have underlying CVD ( heart failure, MI, valvular heart disease)
describe ventricular tachycardia
- if more than 3 consecutive PVS at 100 bpm
- if lasts for more than 30 seconds, requires termination
- torsades de pointes- potentially life threatening
describe ventricular flutter and fibrillation
- lethal
- consequence of ischemic heart disease
- cardiac contraction is not sequential, chaotic
is there tx for arryhthmias
no just aimed at managing symptoms
what are the SE for sodium channel blockers
- bitter taste
- dry mouth
- oral ulcerations
what are the SE of beta blockers
taste changes, lichenoid reactions
what are the SE of potassium channel blockers
- taste abberation
- lichenoid reactions
- angioedema
what are the slow calcium channel blockers
gingival overgrowth
what are the oral anticoagulants
- clopidogrel (Plavix): inhibits platelet agglutination. platelet count not affected
- ASA (aspirin 81mg- low dose): inhibits platelet agglutination, platelet count not affected
- warfarin: vitamin K antagonist, INR monitoring, highly variable
what do anticoagulants do for arrythmias
lower the risks of complications but dont control the arrythmias
what creates opportunities for atherosclerosis and blood clotting
turbulent blood flow and failure to move blood from the atria to the ventricles
what is the therapy for A-fib
to control ventricular rate
- diltiazem ( calcium channel blocker) slows AV nodal conduction as too many electrical signals coming from the fibrillating atria are hitting the AV node per unit time
what are the direct oral anticoagulants
- direct thrombin inhibitor: pradaxa, reversal agent available
- direct factor Xa inhibitors: Xarelto, Eliquis, Savaysa, reversal agents not available
never stop anticoagulation for dental treatment unless:
extensive surgery
what are the non pharmacologic treatments for arrhythmias
- pacemakers
- implanted cardioverter defribrillator: sets pace and shocks
- surgery: tissue resection, cardiac ablation, surgery to address underlying cause such as stenosis
- electrocardioversion and defribrillation: emergency situations, terminate persistant, refractory or lethal arrhythmias
what are the dental treatment considerations with arrhythmias
- what type of arrythmia
- assess comorbidities - CVD and pulmonary
- ROS: palpitations, chest pain, dizziness, shortness of breath, syncope
what are the causes of heart failure
- decreased pumping action
- systemic fluid congestion
- failure of vital organs
what are the results of right side HF
- pulmonary edema
- coughing
- peripheral edema
what are the results of left side HF
- affects all organ systems; decreased kidney function contributes to fluid retention
- pulmonary edema
- coughing
what is the pathophysiology of heart failure
- increased workload -> problems with cardiac muscle
- left ventricle typically fails first- can lead to right ventricular failure
what are the features of heart failure
- reduced CO
- decreased perfusion
- blood backed up in pulmonary vessels- SOB, foamy cough, pulmonary
- pulmonary hypertension
- increased workload on R ventricle
- volume overload: venous congestion, peripheral edema, ascites
- ventricles dilate to try to compensate: activate of RAAS and neurohormonal responses to compensate
what is the equation for ejection fraction
(blood volume pumped out/blood volume in chamber) x 100
what should you consider in past MI greater than 1 month
- severity of cardiac status and comorbidities
- ejection fraction can measure the degree of heart failure
- appropriate management protocols
what does EF measure
percentage of blood that leaves the left ventricle after contraction
describe EF 55%-70%
- pumping ability of the heart: normal
- level of heart failure/effect on pumping: heart function may be normal or heart failure with preserved EF
describe EF 40%-54%
- pumping ability of the heart: slightly blow normal
- level of heart failure/effect on pumping: less blood is available so less blood is ejected from the ventricles. there is a lower than normal amount of oxygen rich blood available to the rest of the body
- may not have symptoms
describe EF 35%-39%
- pumping ability of the heart: moderately below normal
- level of heart failure/effect on pumping: mild heart failure with reduced EF
describe EF less than 35%
-pumping ability of the heart: severely below normal
- level of heart failure/effect on pumping: moderate to severe HF. severe HF increases the risk of life threatening heartbeats and cardiac dyssynchrony
what are the types of heart failure and what is in each category
- systolic failure: reduced left ventricular EF
- diastolic failure: normal left ventricular EF
- cardiac abnormalities: valvular disease, arrhythmias, myocardial necrosis
- decompensation: inability to compensate, increased peripheral blood flow, increased metabolic needs
what are the predisposing factors for HF
- acute CVD: MI
- chronic CVD: HTN, coronary artery disease, arrythmia
what are the results/ signs and ssymptoms of HF
- volume overload
- inadequate perfusion
what are the complications of HF
- cardiac arrest
- MI
- stroke
what are the signs of HF
- rapid , shallow breathing
- inspiratory rales (crackles)
- increased HR
- distended jugular veins
- peripheral edema
- ascites
- cyanosis
- weight gain
- clubbing of fingers
what are the symptoms of HF
- fatigue and weakness
- orthopnea - shortness of breath (dyspnea) in recumbent position
- exercise intolerance
- muscular fatigue
- weight gain
- GI distress- nausea, vomiting and constipation
what are the therapies for stages of HF
- stage A: ACE inhibitors
- stage B: ACE inhibitors, beta blockers
- stage C: diuretics for fluid retention, ACE inhibitors, beta blockers
what is the medical management for HF
- pharmacologic and non-pharmacologic
- patients with severe HF may require cardiac transplantation
- intermediate therapy is the LVAD
in most cases of HF, the dentist will need to obtain a medical consultation with the patients cardiologist to determine:
- the patients physical status
- lab test results
- level of control
- compliance with medications and recommendations
- overall stability
what are the major issues for patients with symptomatic HF
- symptoms can abruptly worsen
- acute failure
- fatal arrhythmia
- stroke
- MI
describe class I HF patients
- physical activity: no limitations
- no dyspnea, fatigue or palpitations with physical activity
describe class II HF patients
- physical activity: slight limitation
- fatigue, dyspnea, palpitations present with physical activity
describe class III HF patients
- physical activity: marked limitation
- lesss than normal physical activity results in symptoms. comfortable at rest
describe class IV HF patients
- physical activity: severely limited, exacerabates symptoms
- symptoms are present at rest
how do we treat each class of HF patients
- class I: routine dental care OK
- class II: med consult required, routine dental care likely OK
- class III and IV: consider referral to specialized care
what are the low level interventions for medical risk categories of dental treatment
- health/medical eval
- exams
- prophy
- radiographs
- optical oral scans
- alginate impressions
what are the moderate level interventions for medical risk categories of dental treatment
- SRP
- simple restorative procedures 1-2 teeth
- simple extractions 1-2 teeth
- restorative impressions needing retractions and longer setting times
what are the high level interventions for medical risk categories of dental treatment
- complex restorative procedures on more than 2 teeth
- multiple extractions
- surgical extractions
- implants placement
- full arch impressions
- dental care under general anesthesia
risk for time of procedure correlates with
risk cateogry
what are some additional HF dental management considerations
- short, stress free appointments
- chair position: HF pt may not be able to tolerate supine position bc pulmonary edema
- if patient is taking digitalis glycoside (digoxin) - positive inotrope: avoid epi because increases the risk for arrhythmia
are there oral manifestations related to HF
no
many of the drugs used to manage HF can cause:
dry mouth, altered taste and oral ulcerative lesions
what is valvular disease
compromised function of the heart valves
what are the AV valves
tricuspid and mitral
what are the semilunar valves
aortic and pulmonary
what is valvular stenosis
do not open properly
what is valvular insufficiency and what is it associated with
- do not close properly
- associated with regurgitation
describe fibrosis in valvular disease
stiff, sclerosis, stenosis causing either stenosis or insufficiency
what is myxomatous degeneration and what does it cause
- benign loose CT tumorous changes where valves become floppy, prolapse, regurgitation
- causes insufficiency
what are the risk factors for valvular heart disease
- conditions: high BP, high cholesterol, Diabetes, rheumatic fever, more than one CVD
- behavioral: unhealthy diet, physical inactivity, obesity, too much alcohol, tobacco use, stress
- family hx: genetics, becoming older, ethnicity
- calcifications
- congenital defects
- infective endocarditis
why is high BP a risk factor for valvular heart disease
- stiffens vessels which reduce blood flow
- risk for stroke, kidney disease and dementia
why is diabetes a risk factor for valvular heart disease
unstable glucose affects healthy myocardium function, angiopathy
what parts of unhealthy diet are risk factors for valvular heart disease
- carbs
- fat
- caffeine
- Na+
why is poor circulation a risk factor for valvular heart disease
poor circulation
why is obesity a risk factor for valvular heart disease
- excess weight stresses heart function
- HTN
- CAD
why is alcohol a risk factor for valvular heart disease
- increases BP
- arryhtmias
what congenital defects are risk factors for valvular heart disease
- bicuspid aortic valve
- mitral valve prolapse
what microbe causes infective endocarditis
staph
what are the signs and symptoms of valvular heart disease
- signs: murmurs, syncope, heart failure, SOB
- symptoms: HF, exercise intolerance, SOB
what is the medical management for valvular heart disease
- tx is mainly surgical
- valve replacement - more common
- predisposition for infective endocarditis
what are the types of valve replacements for valvular heart disease
- mechanical implants: silicone, requires long term anticoagulation
- bioprosthetic implants: allograft, bovine graft, decellurized CT with a less antigenic structural matrix. short term anticoagulation. long term antiplatelet therapy, more preferred
what are the questions for patients with valvular disease
- screening: SOB, chest pain
- have you ever had valve replacement surgery
- do you take a blood thinner
- do you take aspirin or plavix
- does it take a long time for you to stop bleeding after a cut
- have you ever been hospitalized due to bleeding
- have you ever had IE
are there oral manifestations with valvular heart disease
no
what are the bleeding complications with valvular heart disease
- complications from anticoagulation
- complications from antiplatelet therapy
what are the infections complications of valvular heart disease
- risk of developing infective endocarditis
- requires antibiotic prophylaxis when valves have been replaced
what are the drug effects for patients with valvular heart diseae
potential drug interactions from CVD pharmacologic management sespecially when comorbidities are present
what are the dental considerations for valvular heart disease
- assess ability to tolerate care in context of underying condition and comorbidities
- assess bleeding risk: obtain INR day of procedure. have local hemostatic measures in place
- infections: determine need for AB prophylaxis and AB of choice
- drug effects- review adverse drug effects and drug-drug interactions
