Clinical Intelligence · Est. 2017

Marios Tzavelas, MD

Data Scientist | Physician | AI Product Solutions

High-Performance AI & Data Architecture for Complex Systems.

Bridging 5+ years of acute care clinical experience with advanced machine learning, NLP, and data analytics. I combine medical precision with AI solutions to build robust, scalable systems for high-stakes environments.

5+yrs acute-care clinical
4kclinical records modeled
3deployed AI systems
LONGITUDINAL FISSUREfrontalprecentralcentralpostcentralintraparietalsylvianhidden φaligned_output →CEREBRUM · PLATE I
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Centerpiece · Interactive

SEER Breast Cancer Survival Prediction

An end-to-end ML pipeline trained on 4,000+ clinical records using Decision Trees, Naive Bayes, and neural networks. Interact with the widget to render dynamic mortality risk and survival timelines based on engineered clinical features.

Patient Features
Age55yrs
Tumor Size28mm
Stage1· I
Grade1· G1
Mortality Risk ScoreLOW RISK
20/ 100

Simulated ensemble output · Clause threshold >= 60 flags escalation

Kaplan-Meier Survival Curve

5-Year Survival Probability81.0%

S(t) = 1 − R·(1 − e⁻ᵃᵗ) · R = modeled risk coefficient · CI 95% · SEER-selected cohort, t ∈ [0, 60] months

Subsection 2A · Feature Engineering

Feature Engineering: Lymph Node Ratio (LNR) Gauge

Outperforming raw positive node counts in Decision Tree root splits.

Nodes Examined15

Range 1 – 60 · total surgical nodes sampled

Nodes Positive2

Range 0 – 15 · capped at Nodes Examined

Live Formula ReadoutFAVORABLE

LNR = 2 / 15 = 0.133

Lymph Node Ratio = Nodes Positive / Nodes Examined

0.000.250.500.751.00⇢ 0.349
0.133LNR
PRIMARY SPLIT: LOW RISK PATHWAY (LNR ≤ 0.349)

In our decision tree model, raw positive lymph node count was passed over in favor of the engineered Lymph Node Ratio (LNR) as the single most critical root decision boundary. An LNR ≤ 0.349 served as the primary gatekeeper for favorable survival outcomes.

Subsection 2B · Biological vs. Physical

Feature Weight Race: Biology vs. Tumor Size

Standardized Linear Regression Impact on Survival Months.

Physical dimensions (Tumor Size) show a negative impact on survival time (-0.04 months/mm). Click below to integrate molecular biology.

AgeDEMOGRAPHIC
02.0
Raw per-unit impact-0.20 months / year
M StageMETASTATIC
02.0
Raw per-unit impact-6.49 months / metastatic step
Tumor SizePHYSICAL
02.0
Raw per-unit impact-0.04 months / mm
LNRENGINEERED
02.0
Raw per-unit impact-2.29 months / 100% ratio increase
GradeHISTOLOGICAL
02.0
Raw per-unit impact-0.24 months / histological step
Hormone Status scored ordinally: Double Positive → Single Positive → Double Negative; each severity step ≈ −8.57 months.bars: standardized · hover: raw
Deployed Systems

Interactive Project Grid

Three production-grade clinical AI systems. Explore the architecture, the clinical logic, and run a live demo inside each card.

SynthEHR Agentic Generator

Synthetic EMR

A hybrid LLM and rule-based architecture creating deterministic, longitudinal patient records. Engineered with state persistence, temporal reasoning, and Pydantic schemas to eliminate clinical hallucinations.

A two-track pipeline where agentic orchestration meets deterministic rule modules.

  • LLM agent orchestrator + rule-based generator merge
  • Deterministic assembly layer constrains stochastic output
  • Modular resource builders emit FHIR-native structures

RxShield DDI Microservice

FastAPI · SQL

A high-performance drug-drug interaction engine built on FastAPI. Leverages CTE-based self-joins and optimized set-based SQL queries for instant, single-roundtrip multi-drug analysis.

A thin FastAPI service carrying a relational interaction graph in PostgreSQL.

  • FastAPI endpoints with async IO and connection pooling
  • CTE-based self-joins collapse multi-drug checks to one query
  • Set-based SQL keeps latency flat as the regimen grows

Symptom Intake Triage Agent

LangGraph · Ollama

A stateful conversational AI built with LangGraph and Ollama. Features automated symptom extraction, dynamic urgency scoring, and multi-layer clinical safety guardrails.

A stateful graph with a local inference runtime and layered safety valves.

  • LangGraph stateful conversation graph with checkpoints
  • Ollama-hosted local LLM keeps PHI on-device
  • Multi-layer guardrails gate every escalation path
Clinical History

The Diagnostic Timeline

A continuous EKG of my clinical rotations, data and AI roles. Scroll to trace the rhythm from bedside to data science.

06/2025 – 06/2026

Dyania Health

Clinical Data Scientist

Scaled AI EMR processing across hospital networks covering millions of patients. Translated trial protocols into machine-readable logic, boosting speeds by over 5x.

EMRNLPtrials5x
02/2024 – Present

Primovia

Medical Consultant & Web Developer

Designed accessible digital healthcare platforms and formulated growth strategies based on health data trends.

digital healtha11yanalytics
06/2019 – 03/2024

Ahepa University Hospital

Internal Medicine Resident

Executed clinical trials and synthesized complex data in high-pressure ICU, ER, and Cardiology environments.

ICUERCardiology
01/2017 – 03/2019

General Hospital of Kozani & Hellenic Army

Rural Doctor & Medical Officer

Delivered fast-paced emergency management and diagnostic care across operations.

emergencyoperations
9.2 years of continuous bedside — IM · cardiology · ICU · ER · data · AI
Academic Credentials

The Clinical Lab Terminal

A diagnostic audit of my academic and clinical record: MD, data science, biomedical engineering, and GCP. Printed out in real time.

sys_admin@clinical-lab: ~/credentials
Stack

Tech Stack Matrix

Grab a pill. Every skill is draggable. The stack spans clinical standards (FHIR / ICD-10) through statistical modeling and modern cloud-native infra.

Python
R
Pandas
Matplotlib
Seaborn
PyTorch
Scikit-learn
NLP
LLMs
LangGraph
LangChain
RAG
EMR/EHR
FHIR
ICD-10
GCP
FastAPI
PostgreSQL
MongoDB
Git
Legend
Core Data Science5
ML / NLP7
Clinical Standards4
Data & Infra4
Physician-Engineered AI

Engineered for High-Stakes Data.

I enforce strict data integrity, build scalable architectures, and deploy AI that solves structural problems. Open to roles in data science, AI engineering and product roles across all data-intensive sectors. Secure routes below. No chatbots, just a direct line.