Stroke natural history, complications and prognosis

# Overview
Stroke can cause temporary or permanent complications based on the location and time to appropriate treatment. Delayed treatment or sever hemorrhagic or ischemic stroke can lead to death. Other may suffer from Dysphagia, Pneumonia, Myocardial infarction and arrhythmias, need for mechanical ventilation, pulmonary edema, central sleep apnea, urinary incontinence, falls, Musculoskeletal spasticity, Post-stroke seizure, Bowel incontinence, cognitive impairment. Prognosis depends on patient's age and stroke severity based on clinical evaluation and imaging.

# Natural History
Given the ability to alter the natural history of stroke with endovascular thrombectomy, early identification of patients with vessel occlusion is critical. Differentiating acute ischemic stroke (AIS) patients with large vessel occlusions from those without based on clinical presentation is nonetheless challenging due to the variable nature of collateral vasculature and the potential for unique at risk and symptomatic tissue patterning across patients with the same anatomical site of occlusion. Vessel occlusions can also commonly manifest with minimal symptomology.
While not pathognomonic, the clinical presentation of patients with vessel occlusion is nonetheless often stereotyped and anatomically matched to the site of occlusion and downstream affected cerebrum.
Specifically, ICA or proximal MCA occlusions often present with contralateral hemi body and face weakness and/or numbness, contralateral homonymous hemianopsia, and ipsilateral gaze deviation, as well as aphasia for dominant hemispheric lesions and neglect for lesions of the nondominant hemisphere. More nuanced presentations of variable clinical severity and importance are observed with more distal occlusions.
One notable distal occlusion site is the M3 branch to the angular gyrus of the dominant hemisphere. Due to the involvement of this vascular territory in speech processing and complex cognition, focal occlusions in this location are sometimes more aggressively pursued for thrombectomy in an attempt to preserve speech and cognition as compared to similarly distant blockages in arteries supplying less eloquent cortex.

# Complications
The early complications of patients, survived from a stroke is as follows:
- Dysphagia
- Venous thromboembolism
- Pneumonia
- Urinary tract infection
- Myocardial infarction
- Arrhythmias
- Neurogenic cardiac damage
- Need for mechanical ventilation
- Neurogenic pulmonary edema
- Central sleep apnea
- Gastrointestinal bleeding
- Urinary incontinence
- Falls and bone fractures
- Depression
- Post-stroke fatigue
There are also some long-term complications including:
- Musculoskeletal spasticity
- Hemiplegic shoulder pain
- Post-stroke seizure
- Bowel incontinency
- Cognitive impairment

# Prognosis
In the acute phase of stroke, the strongest predictors of outcome are stroke severity and patient age. Stroke severity can be judged clinically, based upon the degree of neurologic impairment (eg, altered mentation, language, behavior, visual field deficit, motor deficit) and the size and location of the infarction on neuroimaging with magnetic resonance imaging (MRI) or computed tomography (CT).
In addition, presence of anemia, atrial fibrillation, cancer, coronary artery disease, dementia, diabetes, heart failure, renal dysfunction, and poor nutrition are among other comorbidities, which can make the prognosis poorer.