For women, the presence of musculoskeletal disease, heart disease, obstructive sleep apnea, cataplexy, doing physical activities close to bedtime and the presence of a mental disorder were significantly associated with having a higher risk of both PLMD and restless legs syndrome.PLMS seems to have an origin in the spinal cord. In fact, PLMS was suggested to be associated with increased spinal reflexes. Manifestations of PLMS seem to occur mostly in disorders associated with dopaminergic dysfunctions.Hypothesis of low ferritin levels in adult population was raised to explain PLMD where increased RLS severity and increased PLMS were significantly correlated with low ferritin levels. Research evidence suggested iron is possibly contributing to PLMD. Thus, lack of iron may induce inhibition of dopamine formation which might underlie PLMS. Diagnosis
People with PLMD often do not know the cause of their excessive daytime sleepiness and their limb movements are reported by a spouse or sleep partner. PLMD cannot be diagnosed by polysomnogram (PSG) alone, it is necessary to obtain a full medical history and taking into account all available information.Polysomnography is recognized as the assessment method which brings most precise information on sleep quality, sleep structure and physiological parameters during sleep (respiration, heart rate, movements). Therefore, diagnostic of PLMD can usually be established only in laboratory settings.
Other, non-invasive tests are better used when the diagnosis or certainty of the diagnosis is not as clear.Indications for cardiac catheterization include the following:
Acute coronary syndromes: ST elevation MI (STEMI), non-ST Elevation MI (NSTEMI), and unstable angina
Evaluation of coronary artery disease as indicated by
Abnormal stress test
As part of the pre-op evaluation for other cardiac procedures (e.g., valve replacement) as coronary artery bypass grafting may be done at the same time
Risk stratification for high cardiac risk surgeries (e.g., endovascular aneurysm repair)
Persistent chest pain despite medical therapy thought to be cardiac in origin
New-onset unexplained heart failure
Survival of sudden cardiac death or dangerous cardiac arrhythmias
Workup of suspected Prinzmetal angina (coronary vasospasm)Right heart catheterization, along with pulmonary function testing and other testing should be done to confirm pulmonary hypertension prior to having vasoactive pharmacologic treatments approved and initiated. to measure intracardiac and intravascular blood pressures
to take tissue samples for biopsy
to inject various agents for measuring blood flow in the heart; also to detect and quantify the presence of an intracardiac shunt
to inject contrast agents in order to study the shape of the heart vessels and chambers and how they change as the heart beats

Pacemakers and defibrillators
Placement of internal pacemakers and defibrillators are done through catheterization as well. An exception to this is placement of electrodes on the outer surface of the heart (called epicardial electrodes). Otherwise, electrodes are placed through the venous system into the heart and left there permanently.